The interpretation timeline
Ephesians 1:18 Douay-Rheims

The eyes of your heart enlightened, that you may know what the hope is of the glory of his inheritance in the saints.

A.D. 220 – 1871 7 witnesses

Patristic

before A.D. 750
220
A.D.
Tertullian Patristic
c. A.D. 150–220
“He likewise will grant "the enlightenment of the eyes of the understanding," who has also enriched our natural eyes with light; to whom, moreover, the blindness of the people is offensive: "And who is blind, but my servants? . In His gift, too, are "the riches (of the glory) of His inheritance in the saints," who promised such an inheritance in the call of the Gentiles: "Ask of me, and I will give Thee the heathen for Thine inheritance.”
Source
407
A.D.
John Chrysostom Patristic
A.D. 347–407
“"Having the eyes of your heart enlightened in the knowledge of Him." He that hath learned what God is, will have no misgiving about His promises, and disbelief about what hath been already brought to pass. He prays, then, that there may be given them "a spirit of wisdom and revelation." Yet still he also establishes it, as far as he can himself, by arguments, and from "already" existing facts. For, whereas he was about to mention some things which had already come to pass, and others which had not as yet happened; he makes those which have been brought to pass, a pledge of those which have not: in some such way, I mean, as this, "That ye may know," saith he, "what is the hope of His calling." It is as yet, he means, hidden, but not so to the faithful. "And," again, "what is the riches of the glory of His inheritance in the saints." This too is as yet hidden. "The riches of the glory," That is, the unutterable glory; for what language shall be adequate to express that glory of which the saints shall then be partakers? None. But verily there is need of grace in order that the understanding may perceive it, and admit even so much as at least one little ray. Some things indeed they knew even before; now he was desirous that they should learn more, and know it more clearly.”
Source

Scholastic

c. 1100 – 1500
1273
A.D.
Thomas Aquinas Catholic
1225–1274
“After the Apostle enumerated the benefits conferred on the Ephesians through Christ, here he shows how his affection grew toward them. This part is divided into three parts: for first he sets forth a commemoration of the good things which he heard about them; second, the due giving of thanks for the benefits received, at "I cease not giving thanks," etc.; third, his prayer for future benefits is added, at "making mention of you," etc. Now the good things which he heard about them are two. One is that by which they are ordered to God, and this is faith, and as to this he says, "therefore I also, hearing of your faith which is in Christ Jesus" — which indeed makes God dwell in man. Below, Ephesians 3:17: "that Christ may dwell through faith in your hearts." Likewise, it purifies hearts. Acts 15:9: "purifying their hearts by faith." Likewise, it justifies without the law. Romans 3:28: "we reckon that a man is justified by faith without the works of the law." The second is that by which they are ordered to their neighbor, and this is love, and as to this he says, "and the love," that is, the works of charity — which love indeed is the spiritual sign that a man is a disciple of Christ. John 13:35: "by this shall all men know that you are my disciples, if you have love," etc. And in the same place, John 13:34: "a new commandment I give you, that you love one another," etc. "The love," I say, "toward all the saints." For all whom we love out of charity, we ought to love either because they are holy, or so that they may be holy. Galatians 6:10: "while we have time, let us work good to all, but especially to those who are of the household of the faith," etc. Then when he says "I cease not," etc., the Apostle gives thanks for the good things and benefits of this kind that he has heard of, saying, "I cease not giving thanks," etc. An objection arises: because he could not always continually give thanks for them. I respond: the Apostle says "I cease not," that is, at the due hours; or, "I cease not" because the disposition of giving thanks for you is habitually in me without ceasing. Colossians 1:9: "we cease not to pray for you, and to ask," etc. Romans 1:9-10: "without ceasing I make mention of you always in my prayers." Consequently the Apostle prays for the benefits to be granted to them in the future, and as to this he says, "making mention of you," etc. And this is divided into three: for first he sets forth certain things which he asks for them; second he explains them, at "unto the knowledge of him," etc.; third he shows the exemplar and form of those things, at "according to the working of his power," etc. He says, therefore, as to the first: I not only give thanks for the past benefits which you have received, and for the good things heard about you, but I also pray that they may altogether increase in the future. "Making mention of you in my prayers" — for these things, namely, "that the God of our Lord Jesus Christ, the Father of glory," etc. Here it must be known that our Lord Jesus Christ is both God and man. And insofar as he is man, he has God, since he is composed of soul and body, to each of which — since they are creatures — it belongs to have God; but insofar as he is God, he has a Father. John 20:17: "I ascend to my Father and your Father, my God and your God." Likewise also, insofar as he is God, he is the glory of the Father. Hebrews 1:3: "who, being the splendor of glory," etc. He is also our glory, because he himself is eternal life. 1 John, last chapter, 20: "that we may be in his true Son; this is the true God, and eternal life." Thus, therefore, he says "the God of our Lord Jesus Christ" according as he is man, and "the Father of the same" according as he is God; the Father, I say, "of glory," namely of Christ, who is his glory — Proverbs 10:1: "a wise son is the glory of his father," etc. — and Father of our glory, insofar as he gives glory to all. Then when he says "may give unto you," etc., he sets forth the things which he asks for, which are two. Here it must be known that certain gifts are common to all the saints, namely those which are necessary for salvation, such as faith, hope, and charity — and these they had, as is already clear. But there are other, special gifts, and as to these he prays for them. First indeed for the gift of wisdom, and as to this he says, "that he may give you the spirit of wisdom," which no one can give except God. Wisdom 9:17: "and who shall know your thought, unless you give wisdom, and send your holy spirit from on high?" Second, he prays for the gift of understanding, and this consists in the revelation of spiritual secrets, on account of which he says, "and of revelation," which also is from God alone. Daniel 2:28: "there is a God in heaven who reveals mysteries." Now he explains what these things are which he asks for: first, what pertains to the gift of wisdom; second, what pertains to the gift of understanding, at "that you may know what is the hope," etc. Now to the gift of wisdom pertains the knowledge of divine things. Hence to ask for the gift of wisdom is to ask that they may have the knowledge of God, and this he asks at "unto the knowledge of God," etc., as if to say: this I ask, that through the spirit of wisdom you may have the eyes of your heart enlightened unto the knowledge — namely, the clearer knowledge — of him, namely of God. Psalm 12:4: "enlighten my eyes," etc. This is against those who have their eyes enlightened only to know temporal things, whereas it is much more necessary, and indeed glorious, to know God. Jeremiah 3:23f.: "let not the wise man glory in his wisdom, and let not the rich man glory in his riches; but let him who glories, glory in this, that he knows and understands me." To the gift of understanding he sets forth three things pertaining: one as to the present state, and two as to the future. To the present state indeed pertains hope, which is necessary for salvation. Romans 8:24: "for by hope we are saved," etc. And as to this he says, "that you may know what," that is, how great, "is the hope of his calling," that is, the power of hope, and how great a thing it concerns. Which indeed is also the greatest, because it concerns the greatest things. 1 Peter 1:3: "he has regenerated us unto a living hope, through the resurrection of Jesus Christ from the dead," etc. And it is the strongest of the virtues. Hebrews 6:18: "that we may have the strongest comfort, we who have fled to hold fast the hope set before us, which we have as an anchor of the soul," etc. But because the things we hope for concern the future life, therefore the other two pertain to the future life. One indeed pertains to all the just in common, which is the essential reward, and as to this he says, "and what are the riches of the glory," etc. Here he sets forth four things pertaining to those gifts. The first is that they are most abundant, and as to this he says "riches." Proverbs 1:33: "he shall enjoy abundance, the fear of evils being removed." Psalm 111:3: "glory and riches are in his house," etc. Proverbs 8:18: "with me are riches and glory," etc. Second, that they are most glorious, and as to this he says "of glory." Romans 2:10: "but glory, and honor, and peace to every one that works good," etc. Third, that they are most stable, and as to this he says "of the inheritance." For those things which are hereditary are possessed stably. Ecclesiasticus 31:11: "his goods are established in the Lord." Psalm 15:5: "the Lord is the portion of my inheritance and of my cup," etc. Fourth, that they will be intimate, and as to this he says "in the saints." Romans 8:18: "the sufferings of this time are not worthy," etc. 2 Corinthians 4:17: "works in us, beyond measure, a weight of glory in sublimity." The other thing which he sets forth pertaining to future glory is that which specially pertains to the apostles, hence he says, "and what is" (supply: "that you may know") "the surpassing greatness of his power toward us," namely, the apostles. As if to say: although he abundantly bestows the riches of glory on all the saints, yet he will bestow them more surpassingly on the apostles. For the greatness of power is shown in its effect. Hence the more the effect of the divine power is found in someone, the greater the divine power is shown to be there, although in itself it is one and undivided. And therefore, because a greater effect of the divine power is in the apostles, therefore the greatness of the power will be in them. And that the effect is greater in them he shows, saying, "who believe," that is, who are the firstfruits of believers. 2 Corinthians 4:13f.: "we believe, for which reason we also speak, knowing that he who raised up Jesus will also raise us up with Jesus." On account of which he said, 2 Timothy 1:12: "I know whom I have believed," etc. Therefore those among you through whom others were instructed and called to the faith, such as teachers, will be rewarded more preeminently; because, as is said in the Gloss, the greatest teachers will have a certain increase of glory beyond that which all will have in common, on account of which, Daniel 12:3: the learned are likened to the splendor of the firmament, but teachers are likened to the stars: "and they that are learned shall shine as the splendor of the firmament, and they that instruct many unto justice, as stars for perpetual eternities."”

Post-Reformation

c. 1650 – 1900
1771
A.D.
John Gill Reformed
1697–1771
“The eyes of your understanding being enlightened,.... By the Spirit of God already, to see the exceeding sinfulness of sin; the insufficiency of their own righteousness; the beauty, glory, fulness, and suitableness of Christ, as a Saviour; the excellency, truth, and usefulness of the doctrines of the Gospel; in which their understandings were before dark, but now had light into them: wherefore these words are not to be considered as part of the apostle's petitions, but rather as what was taken for granted by him; and are to be put into a parenthesis, and the following words to be joined in connection with the preceding verse; unless it should be thought, that the apostle prays for greater illuminations, and for more spiritual light, and that the eyes of their understandings might be more and more enlightened; the phrase, , , "the eye of the understanding", is Rabbinical, and often to be met with in Jewish writings (f); the Alexandrian copy, and several others, the Complutensian edition, the Vulgate Latin, and all the Oriental versions, read, "the eyes of your heart"; and to, , "the eyes of the hearts, or minds", is a phrase used by the Jewish writers (g): that ye may know what is the hope of his calling; by which is meant, the effectual calling of the saints; which is not a call to an office, or a call merely by the external ministry of the word; but which is internal, special, powerful, high, and heavenly: and this is the calling of God, of which he is the author; who calls with an holy calling, unto eternal glory by Christ Jesus; and which is without repentance: and the hope of this calling, is either eternal happiness, which is the thing hoped for; or Christ, who is the ground and foundation of it; or the grace of hope, which is exercised on both; or all three: for hope of eternal glory, as it is founded on Christ, may be said to be the hope of the calling of God, because it is wrought in the soul at the time of the effectual calling, and what saints are then called to the exercise of; and calling grace, is an encouragement to hope for eternal life; since whom God calls, he justifies and glorifies: and now the apostle prays, that these saints who were called by the grace of God, might know more of Christ, the foundation of their hope; and what that is they are hoping for, and more and more what it is to hope for the same, upon the view of Christ's person, blood, and righteousness: and what the riches of the glory of his inheritance in the saints; the saints themselves are the Lord's portion, and the lot of his inheritance, in whom he is, and will be abundantly glorified; but here it rather seems to design the heavenly inheritance before spoken of, of which the Spirit is the earnest; and this is the Lord's, it is of his preparing, and it is his gift, and a very rich and glorious inheritance it is: hence it is not only signified by mansions, and everlasting habitations, by an house, and by a city, but by a kingdom; the riches of grace are preparatory to it, and the riches of glory are comprised in it; and this is in, or among the saints, who only have a right unto it, and a meetness for it; and what this inheritance is, with the riches and glory of it, will not be fully known in this life; and indeed but little of it is known; so that such a petition as this is always proper and pertinent. (f) Zohar in Deut. fol. 119. 3. Jetzirah, p. 22. 78. Ed. Rittangel. R. Levi ben Gersom in Gen. fol. 14. 3. & Philo de opificio Dei, p. 15. (g) Bechinat Olam, p. 260.”
Source
1832
A.D.
Adam Clarke Methodist
1762–1832
“The eyes of your understanding being enlightened - The understanding is that power or faculty in the soul by which knowledge or information is received, and the recipient power is here termed the Eyes of the understanding; and we learn from this that ὁπερ ὁ οφθαλμος εν τῳ σωματι, τουτο ὁ νους εν τῃ ψυχη, as Philo expresses it: What the eye is to the body, the understanding is to the soul; and that as the eye is not light in itself, and can discern nothing but by the means of light shining, not only on the objects to be viewed, but into the eye itself; so the understanding of man can discern no sacred thing of or by itself, but sees by the influence of the Spirit of wisdom and revelation; for without the influence of God's Holy Spirit no man ever became wise unto salvation, no more than a man ever discerned an object, (no matter how perfect soever his eye might have been), without the instrumentality of light. Instead of της διανοιας, of your understanding, της καρδιας, of your heart, is the reading of ABDEFG, and several others; also both the Syriac, all the Arabic, the Coptic, the Ethiopic, Armenian, Sahidic, Slavonian, Vulgate, and Itala, besides several of the fathers. The eyes of your Heart is undoubtedly the true reading. The hope of his calling - That you may clearly discern the glorious and important objects of your hope, to the enjoyment of which God has called or invited you. The riches of the glory of his inheritance - That you may understand what is the glorious abundance of the spiritual things to which you are entitled, in consequence of being made children of God; for if children, then heirs, heirs of that glorious inheritance which God has provided for the saints - for all genuine Christians, whether formerly Jews or Gentiles. On the chief subject of this verse, see the notes on Gal 4:6, Gal 4:7 (note).”
Source
1863
A.D.
1871
A.D.
1871
“understanding--The oldest manuscripts, versions, and Fathers, read "heart." Compare the contrary state of unbelieving, the heart being in fault (Eph 4:18; Mat 13:15). Translate, "Having the eyes of your heart enlightened" (Eph 5:14; Mat 4:16). The first effect of the Spirit moving in the new creation, as in the original physical creation (Gen 1:3; Co2 4:6). So THEOPHILUS to AUTOLYCUS (1.3), "the ears of the heart." Where spiritual light is, there is life (Joh 1:4). The heart is "the core of life" [HARLESS], and the fountain of the thoughts; whence "the heart" in Scripture includes the mind, as well as the inclination. Its "eye," or inward vision, both receives and contemplates the light (Mat 6:22-23). The eye is the symbol of intelligence (Eze 1:18). the hope of his calling--the hope appertaining to His having called you; or, to the calling wherewith He has called you. and--omitted in the oldest manuscripts and versions. riches of the glory-- (Col 1:27). his inheritance in the saints--The inheritance which he has in store in the case of the saints. I prefer explaining, "The inheritance which He has in his saints." (See on Eph 1:11; Deu 32:9).”
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.