The interpretation timeline
Revelation 4:6 Douay-Rheims

And in the sight of the throne was, as it were, a sea of glass like to crystal; and in the midst of the throne, and round about the throne, were four living creatures, full of eyes before and behind.

A.D. 202 – 1871 7 witnesses 8 excerpts

Patristic

before A.D. 750
202
A.D.
Irenaeus Patristic
c. A.D. 130–202
“It is not possible that the Gospels can be either more or fewer in number than they are. For, since there are four zones of the world in which we live, and four principal winds, while the Church is scattered throughout all the world, and the "pillar and ground" of the Church is the Gospel and the spirit of life; it is fitting that she should have four pillars, breathing out immortality on every side, and vivifying men afresh. From which fact, it is evident that the Word, the Artificer of all, He that sitteth upon the cherubim, and contains all things, He who was manifested to men, has given us the Gospel under four aspects, but bound together by one Spirit. As also David says, when entreating His manifestation, "Thou that sittest between the cherubim, shine forth." For the cherubim, too, were four-faced, and their faces were images of the dispensation of the Son of God. For, [as the Scripture] says, "The first living creature was like a lion," symbolizing His effectual working, His leadership, and royal power; the second [living creature] was like a calf, signifying [His] sacrificial and sacerdotal order; but "the third had, as it were, the face as of a man,"-an evident description of His advent as a human being; "the fourth was like a flying eagle," pointing out the gift of the Spirit hovering with His wings over the Church. And therefore the Gospels are in accord with these things, among which Christ Jesus is seated. For that according to John relates His original, effectual, and glorious generation from the Father, thus declaring, "In the beginning was the Word, and the Word was with God, and the Word was God." Also, "all things were made by Him, and without Him was nothing made." For this reason, too, is that Gospel full of all confidence, for such is His person. But that according to Luke, taking up [His] priestly character, commenced with Zacharias the priest offering sacrifice to God. For now was made ready the fatted calf, about to be immolated for the finding again of the younger son. Matthew, again, relates His generation as a man, saying, "The book of the generation of Jesus Christ, the son of David, the son of Abraham;" and also, "The birth of Jesus Christ was on this wise." This, then, is the Gospel of His humanity; for which reason it is, too, that [the character of] a humble and meek man is kept up through the whole Gospel. Mark, on the other hand, commences with [a reference to] the prophetical spirit coming down from on high to men, saying, "The beginning of the Gospel of Jesus Christ, as it is written in Esaias the prophet,"-pointing to the winged aspect of the Gospel; and on this account he made a compendious and cursory narrative, for such is the prophetical character. And the Word of God Himself used to converse with the ante-Mosaic patriarchs, in accordance with His divinity and glory; but for those under the law he instituted a sacerdotal and liturgical service. Afterwards, being made man for us, He sent the gift of the celestial Spirit over all the earth, protecting us with His wings. Such, then, as was the course followed by the Son of God, so was also the form of the living creatures; and such as was the form of the living creatures, so was also the character of the Gospel. For the living creatures are quadriform, and the Gospel is quadriform, as is also the course followed by the Lord.”
Source
303
A.D.
c. A.D. 250–303
“"And before the throne there was, as it were, a sea of glass like to crystal." That is the gift of baptism which He sheds forth through His Son in time of repentance, before He executes judgment. It is therefore before the throne, that is, the judgment.And when he says a sea of glass like to crystal, he shows that it is pure water, smooth, not agitated by the wind, not flowing down as on a slope, but given to be immoveable as the house of God."And round about the throne were four living creatures." The four living creatures are the four Gospels.”
Source
“Now is manifested the reason of the truth why the fourth day is called the Tetras, why we fast even to the ninth hour, or even to the evening, or why there should be a passing over even to the next day. Therefore this world of ours is composed of four elements-fire, water, heaven, earth. These four elements, therefore, form the quaternion of times or seasons. The sun, also, and the moon constitute throughout the space of the year four seasons-of spring, summer, autumn, winter; and these seasons make a quaternion. And to proceed further still from that principle, lo, there are four living creatures before God's throne, four Gospels, four rivers flowing in paradise; four generations of people from Adam to Noah, from Noah to Abraham, from Abraham to Moses, from Moses to Christ the Lord, the Son of God; and four living creatures, viz., a man, a calf, a lion, an eagle; and four rivers, the Pison, the Gihon. the Tigris, and the Euphrates. The man Christ Jesus, the originator of these things whereof we have above spoken, was taken prisoner by wicked hands, by a quaternion of soldiers. Therefore on account of His captivity by a quaternion, on account of the majesty of His works,-that the seasons also, wholesome to humanity, joyful for the harvests, tranquil for the tempests, may roll on,-therefore we make the fourth day a station or a supernumerary fast.”
Source

Post-Reformation

c. 1650 – 1900
1771
A.D.
John Gill Reformed
1697–1771
“And before the throne there was a sea of glass like unto crystal,.... By which is meant, not heaven, nor the souls of the blessed there, nor the multitude of the holy angels, nor the first converts to Christianity at Jerusalem; for those that got the victory over the beast are said to stand upon this sea, Rev 15:2, which these senses, especially the three last, will by no means admit of. Some by it understand the world, which may be compared to a "sea", for the multitude of people in it, as many waters in this book signify people and nations, Rev 17:15; and to a sea of glass, which is brittle, for the frailty and transitoriness of the world, of the fashion of it, and of men and things in it; and to the clear "crystal", because all things in it are open and manifest to the omniscient eye of God; but the world, and men of it, used not to be compared to a still and quiet sea, as this is, but to one disturbed and troubled by winds and tempests, whose waters cast up mire and dirt, Isa 57:20. Others think the ordinance of baptism is designed, of which the Red sea, through which the Israelites passed under the cloud, was an emblem; and which may be compared to a "sea of glass", for its transparency, it clearly expressing the sufferings, burial, and resurrection of Christ; and to crystal, for its purity; and to all this for its cleansing nature, as it leads unto the blood of Christ; and its being before the throne may denote its being the way of entrance into the Gospel church. Others think the blood of Christ is meant, in allusion to the brazen sea in the tabernacle, which was made of the looking glasses the women brought, and for the priests to wash in, before they entered on business, Exo 30:18, and to the molten sea in the temple, which was for the same purpose, Kg1 7:23. Christ's blood is the fountain opened to wash in for sin, and may be compared to a sea for its abundant efficacy in cleansing from all sin; and it is this which makes way to the throne, and to him that sits on it; and is a special privilege enjoyed by those who come to Mount Zion, or into a Gospel church state; there is always this laver to wash their garments in, and make them white: though this sea, being of glass, seems not so much designed to wash in; and therefore rather I think by it is meant the Gospel, compared to a "sea" for the deep things of God and mysteries of grace which are in it; to a sea of "glass", because in it is beheld, as in a glass, the glory of the Lord, of his person, office, and righteousness, as well as many other wondrous things; and to one like "crystal", for the clearness, perspicuity, and evidence of the truths contained in it; and to a, fixed, still; and quiet sea, because it is the Gospel of peace, love, grace, and mercy, and brings peace, joy, and tranquillity to troubled minds, when the law works wrath: but here are no tossing, foaming, raging waves of wrath, and fury, but all smooth, stable, solid, tranquil, and quiet. And this is said to be before the throne, where the rainbow of the covenant is, of which the Gospel is a transcript; and where the four and twenty elders, or members of churches be, for their delight and comfort; and where the seven spirits of God are, to furnish men with gifts to preach it; and where the four living creatures, or ministers of the word, have their place, who officiate in it. Agreeably to this figurative way of speaking, the Jews call (p) the law, , "the sea of the law", and the "sea of wisdom"; and frequently give the characters of such and such a doctor, as being very expert and conversant , "in the sea of the Talmud", or "doctrine" (q). The Alexandrian copy, the Complutensian edition, the Vulgate Latin and Syriac versions, read, "there was as a sea of glass", somewhat that looked like one. The word "glass" is left out in the Ethiopic version, but very aptly is it so described, the colour of the sea being sometimes green like that of glass. And in the midst of the throne, and round about the throne, were four beasts; or "living creatures", as the word may be better rendered, agreeably to Eze 1:5, to which reference is here had; and by whom are meant not the angels, though there are many things which agree with them; they are said to be the "four spirits" of the heavens, which go forth from standing before the Lord of all the earth, Zac 6:5. They may be rightly called living creatures, since they live a most happy life in heaven; their situation is before the throne, and in the presence of God; and their being so sedulous, diligent, and watchful in doing the will of God, may be signified by their being "full of eyes behind, and before, and within"; their strength may be fitly expressed by "the lion"; their indefatigableness in the service of God, by "the ox": their wisdom, prudence, and knowledge, by "the face of a man"; and their swiftness in obeying the divine commands by "the flying eagle"; their number of wings agrees with that of the seraphim in Isa 6:2; to which the allusion seems to be; and their work, in continually ascribing glory to God, suits with them: to which may be added, that the Jews often speak of four angels, , "round about his throne", that is, the throne of God; whose names are Michael, Gabriel, Uriel, and Raphael; the three first they place in this manner, Michael at his right hand, Uriel at his left, and Gabriel before him (r). Sometimes thus, Michael on his right hand, Gabriel on his left, Uriel before him, and Raphael behind him, and the holy blessed God in the middle; and they are expressly called (s) by them the four living creatures, meaning in Ezekiel's vision; and they make mention of the intellectual living creatures which are , "round about the throne" (t). Notwithstanding all this, the angels cannot be intended, because these four living creatures are said to be redeemed by the blood of Christ, and are distinguished from angels in Rev 5:8; nor are the four Gospels, with the four evangelists, here meant; for whatever agreement may be fancied there is between these, and the likeness of the living creatures; as that Matthew may be signified by the creature that has the face of a man, because he begins his Gospel with the genealogy of Christ, as man; and Mark by the lion, because he begins his Gospel with the voice of one crying in the wilderness; and Luke by the ox, because he begins his Gospel with an account of Zacharias the priest, offering in the temple; and John by the eagle, because he begins his Gospel, the first face or leaf of it, in a very high style, and with the divinity of Christ: and with what truth soever it may be said of these that they are full of divine light and knowledge, and swiftly spread it in the world, and are continually giving glory to God; yet it cannot be said of them, with any propriety, as is said of these four living creatures, that they fall down before God, and worship him, and are redeemed by the blood of the Lamb: besides, these four are represented as calling to John at the opening of the first four seals, to come and see what was to be seen; and one of them is said to give to the seven angels the vials of wrath to pour out, Rev 5:8, to which may be added, that this sense is attended with this inconvenience, that it makes John to be one of the four creatures which he saw: nor are four particular apostles, as Peter and John, Paul and Barnabas, pointed at, as others think; nor the pure apostolical church, for the church is represented by the four and twenty elders, and these four living creatures are distinguished from the hundred and forty four thousand on Mount Zion, in Rev 14:1. Dr. Goodwin has a very ingenious thought upon these words, could it be supported; he thinks that these four living creatures design the four officers in the Christian church, the ruling elder, the pastor, the deacon, and the teacher; the ruling elder by the "lion", who needs courage to deal with men in case of sins; the pastor by the "ox", for his laboriousness in treading out the corn; the deacon by that which has the "face of a man", it being necessary that he should be merciful and pitiful to the poor, as is the heart of a man; and the teacher by the "flying eagle", who is quick to espy errors, and soars aloft into high mysteries: but then it should be observed, that there is no such officer ass ruling elder in the church, distinct from the pastor; and that the pastor and teacher are one; so that there are but two sorts of officers in the church, pastor, and deacon; see Phi 1:1; to which may be added, that the four living creatures are all in the same situation, and are alike full of eyes, and have the same number of wings, and are employed in the same work; all which cannot be said equally of church officers. By these four living creatures, I apprehend, we are to understand the ministers of the Gospel in general, in the successive ages of the church, to whom all the characters do well agree. And though they may not be all found in everyone, at least not in all alike, yet thou are in one or another of them, and in them as together considered. They are said to be "four", being fewer in number than the members of the church, which are signified by the twenty four elders, and yet a sufficient number; and in allusion to the four standards of the camp of Israel in the wilderness, to which there seems to be some reference in the whole of this account; as the tabernacle there was placed in the midst, so the throne of God here; as the priests and Levites were round about that, so the four and twenty elders here; as there were seven lamps, over against the candlestick in the tabernacle, continually burning, so there are seven spirits here before the throne; and as there were four princes, who were standard bearers, placed at the four corners of the camp, so here four living creatures, or ministers of the word, who are standard bearers: the standard of Judah, with Issachar and Zabulon under him, was at the east of the tabernacle; and Ephraim, with Manasseh and Benjamin, at the west; Reuben, with Simeon and Gad, at the south; and Dan, with Asher and Naphtali, at the north; and the Jewish writers say (u), that on Judah's standard was the figure of a lion, on Ephraim's the figure of an ox, on Reuben's the figure of a man, and on Dan's the figure of an eagle; and to which the four living creatures are likened here. And this number "four" may be the rather mentioned, with respect to the four parts of the world, and corners of the earth, whither the ministers of the Gospel are sent to preach, and whither their commission reaches; there being of the elect of God in all parts to be gathered in by their ministry: and very properly may they be called "living creatures", because they are alive in themselves, being quickened by the Spirit of God; or otherwise they would not be fit for their work; and because their work requires liveliness in the exercise of grace, and fervency in the performance of duty: and because they are a means in the hand of God of quickening dead sinners, and of reviving drooping saints by the word of life, which they hold forth: the situation of these four living creatures agrees with them, who are said to be both in the midst of, and round about the throne, and so were nearer to it than the four and twenty elders, and were between that and them; as the ministers of the Gospel are set in the first place in the church; have nearness to God, and much of his presence, which is particularly promised them; and stand between God and the people, and receive from the one, and communicate to the other, and lead on the worship of God, as these four do; see Rev 4:9. And these are said to be full of eyes; of spiritual light, and evangelical knowledge; and they have need of all the eyes they have to look into the Scriptures of truth, to search and pry into them, and find out the sense and meaning of them; to overlook the flock committed to them, they have taken the oversight of; to look to themselves, their doctrine, and their conversation; to espy enemies and dangers, and give notice of them to the churches; to look to God upon the throne, and to the Lamb in the midst of it, for fresh supplies of gifts and grace; and to see to it, that all their ministrations tend to the glory of God, the honour of a Redeemer, and the good of souls. And they had eyes before and behind; "before" them, to look to the word of God, and the deep things in it, which continually lies before them, and to the things that are yet to come relating to the kingdom and church of Christ; and "behind" them, to observe how all sacrifices and types, predictions and promises, have had their accomplishment in Christ; they have eyes before them to watch over the church they are in the midst of, and which is the flock that is before them; and eyes behind, to guard against Satan and his emissaries, false teachers, who sometimes slyly and secretly come upon the back of them; they have eyes before them, to look to him that sits upon the throne, on whom their dependence, and from whom their expectations are; and they have eyes behind them, to look on the four and twenty elders, the members of the churches, to whom they minister. (p) Zohar in Numb. fol. 90. 3. & 92. 1. & in Lev. fol. 24. 3. & in Deut. fol. 118. 4. Tikkune Zohar apud Rittangel. not. in Jetzira, p. 133, 134. (q) Ganz. Tzemach David, par. 1. fol. 46. 2. & 47. 1, 2. (r) Bemidbar Rabba, sect 2. fol. 179. 1. Vid. Pirke Eliezer, c. 4. (s) Zohar in Numb. fol. 91. 3. (t) Raya Mehimna in Zohar in ib. fol. 95. 4. (u) Aben Ezra in Numb. ii. 2.”
1832
A.D.
Adam Clarke Methodist
1762–1832
“Four beasts - Τεσσαρα ζωα· Four living creatures or four animals. The word beast is very improperly used here and elsewhere in this description. Wiclif first used it, and translators in general have followed him in this uncouth rendering. A beast before the throne of God in heaven sounds oddly.”
1849
A.D.
1774–1849
“. A sea of glass, like crystal, calm and transparent, and may signify that the saints had passed a boisterous sea of troubles in this world, which is now changed into everlasting tranquillity. — Four living creatures, or animals. Alcazar (p. 364) takes notice of thirty different expositions of these animals. He understands the apostles, bishops, and preachers of the Christian faith: others, four of the chief Angels or celestial spirits. Several others expound them of the four evangelists: yet this was before St. John himself had written his gospel. (Witham) — The extensive sea of glass, here described transparent as crystal, represents what may be called the floor of heaven. Before the throne and round it stand four living creatures, of an extraordinary shape, which denote the four great prophets, Isaias, Jeremias, Ezechiel, and Daniel. Their bodies are described full of eyes, both before and behind, an emblem of their prophetic sight, that penetrates into all ages past, present, and to come. And their being also full of eyes within, indicates that their extensive knowledge arises from an interior divine inspiration. They have each six wings, in the same manner as the seraphim appeared to the prophet Isaias. (Chap. vi. 2.) Some have imagined these four symbolical animals to represent the four evangelists; but we think improperly, as St. John was still living and there present in person. The first animal is here said to resemble a lion, the king of beasts, because the prophet Isaias, represented by it, was descended of the royal race of David. The second animal resembles a calf, and represents the prophet Jeremias in his character of priest; the calf, which was the principal victim in Jewish sacrifices, being on that account the emblem of the priesthood. The third animal, exhibiting Ezechiel, has the countenance of a man; because God, in speaking to that prophet, always addresses him by the name of son of man. The fourth animal, denoting Daniel, resembles a flying eagle, on account of the sublime oracles of this prophet, who soars to the highest objects, and views the succession of all the great empires that were to rise up in the world to the end of time. Probably these four principal prophets are to be understood to represent all the prophets of the old law. (Walmesley)”
Source
1871
A.D.
1871
“Two oldest manuscripts, A, B, Vulgate, Coptic, and Syriac read, "As it were a sea of glass." like . . . crystal--not imperfectly transparent as the ancient common glass, but like rock crystal. Contrast the turbid "many waters" on which the harlot "sitteth" (Rev 17:1, Rev 17:15). Compare Job 37:18, "the sky . . . as a molten looking-glass." Thus, primarily, the pure ether which separates God's throne from John, and from all things before it, may be meant, symbolizing the "purity, calmness, and majesty of God's rule" [ALFORD]. But see the analogue in the temple, the molten sea before the sanctuary (see on Rev 4:4, above). There is in this sea depth and transparency, but not the fluidity and instability of the natural sea (compare Rev 21:1). It stands solid, calm, and clear, God's judgments are called "a great deep" (Psa 36:6). In Rev 15:2 it is a "sea of glass mingled with fire." Thus there is symbolized here the purificatory baptism of water and the Spirit of all who are made "kings and priests unto God." In Rev 15:2 the baptism with the fire of trial is meant. Through both all the king-priests have to pass in coming to God: His judgments, which overwhelm the ungodly, they stand firmly upon, as on a solid sea of glass; able like Christ to walk on the sea, as though it were solid. round about the throne--one in the midst of each side of the throne. four beasts--The Greek for "beasts," Rev 13:1, Rev 13:11, is different, therion, the symbol for the carnal man by opposition to God losing his true glory, as lord, under Him, of the lower creatures, and degraded to the level of the beast. Here it is zoon, "living creatures"; not beast.”
Source

Undated

date unknown
date
unknown
Glossa Ordinaria Medieval
“In the sight. Because they understand the sacrament and the reality of the sacrament, and receive none but those whom they have seen and known to be fit. A sea of glass. Baptism, bright with the sincerity of faith, after which the elect are led by the fire of tribulation to the firmness of good works, as crystal hardens out of water. In the midst. He describes that a certain level space appeared, after the likeness of a great judge, who has a broad and spacious open place, where he sits and judges judgments. Of the seat. By the name of the seat is understood Jerusalem, or the supporters, as a man, as a calf, as a lion, as an eagle. Four. Because of the office of the fourfold preaching. Living creatures. These well represent Christ, who was born, suffered, rose again, ascended. The faithful also are rational and gentle, as a man; treading down adversities without terror, as a lion; mortifying themselves, as a calf; seeking heavenly things, as an eagle. Full of eyes. Mindful of past sins, and guarding themselves for the time to come; or having knowledge of those things which God has done or will do at the end of the world; or they please God and men.”
Source
Modern · 1953 →

The in-app commentary runs from the Fathers to the early-modern record, then stops — that's where the public-domain sources end, not where the reading does. For the modern reading, follow the sources directly.