Ps 18:2

“The days and the nights teach those people who desire to be taught what ineffable wisdom, what incomprehensible power God has, who has measured out the intervals of time for them. If there were no one who would determine the space and the intervals for the seasons, but they existed in a thoughtless and unconsidered way by chance, it would happen that the days would not be ordered in equal spaces through the ages and there would be a confusion of things, and likewise the times of the nights would pass by chance or happenstance. Even the state of related matters would be disordered because of thoughtless chance, and confusion would follow the confused matter; but … reason rules the right order, and wisdom administers harmony and order. There are mutual changes and alterations; for the days, as the nights yield, are longer, and then the nights claim their space, rightfully due and given mutually, having been increased by winter and season. These things, I say, are not only voiced, but as they announce the knowledge of God to people they declare that most wise order of all things constituted by God. So the voices of the days and nights, by their very work being done, call out to them who are able to hear as their teaching reaches all ears. And the universe that is inhabited by people is replete with songs of this type and like choruses.”

“Now, where there is order there is also proof of the one determining order, and there too denial of being self-made, since what is not done by anyone cannot show order. All these visible things surely illustrate order. So he is saying, "They announce some pattern and cry aloud the order of the orderer and the folly of the notion of being self-made."”

“"Day unto day utters word" [Psalm 19:2]. To the spiritual the Spirit gives out the fullness of the unchangeable Wisdom of God, the Word which in the beginning is God with God. [John 1:1] "And night unto night announces knowledge." And to the fleshly, as to those afar off, the mortality of the flesh, by conveying faith, announces future knowledge.”

“The ordained succession of night and day illustrates the boundaries set by the Creator … the visible things are inanimate, being a kind of mask that teaches everyone to be led from visible things to the invisible God and to offer singing to him … by putting forth neither words nor verbal expressions but the norm, and demonstrating their own order, they summon all land and sea to the divine singing.”

“The heavens recite the glory of God The Psalmist himself explains the matter: There is neither speech nor words. They do not speak with people but since “their line goes forth throughout the earth” and they give light to the people, thereby the creatures recite the glory of God and give thanks and bless [Him] for the luminaries. and the sky tells of the work of His hands The stars and planets, which are the work of the hands of the Holy One, blessed be He, and which are there, as it is stated (in Gen. 1:17): “And God placed them in the firmament of the heavens,” whence they proclaim His glory.”

“The heavens declare the glory of God: – There are interpreters (Targumist and others) who take this as like “Or speak to the earth,and it shall teach thee” (Job 12:8), and “Ask now the beasts, and they shall teach thee” (ibid. 7); and so The heavens declare, for from the wonders and mighty works which man sees in the heavens he declares the glory of God. And this is what he (means when he) says: There is no speech nor words; Their voice cannot be heard, suggesting not that they declare in words, but from what man sees in them the sons of men declare the glory of God. We are able to explain declare with reference to the heavens and the firmament themselves, for by their course and circuit in an appointed order the glory of God – Blessed be He! – is seen; and that is the “declaring” and “telling,” on the analogy of “He sendeth out His commandment upon earth; His word runneth very swiftly.” (Ps. 147:15.) And when he says: There is no speech nor words (he means) no words like the words of men, but the work they do stands for the words, and constitutes the “declaring” and the “telling”; and so he says: And their speech to the end of the world. The great teacher of righteousness, the great sage our Rabbi Moses, has interpreted (Guide for the Perplexed, 2. 5) “declare” of the heavens, for his opinion and that of the Philosophers is that the spheres are living intelligences, serving God and praising Him with great praise, and singing His glory in great and mighty songs. And so he says: The heavens declare the glory of God; And the firmament telleth His handywork, notwithstanding that the “declaring” and the “telling” are not with mouth and tongue. This is what he (means when he) says: There is neither speech nor language; Their voice cannot be heard, but the “declaring” and the “telling” are to them like an image of the words and praises which a man forms in his mind without their actual issuing forth in speech. And the firmament telleth His handywork: – A repetition, for it is equivalent to The heavens declare the glory of God; for the heavens are called “firmament,” as it is said (Dan. 12:3) “as the brightness of the firmament” etc.; “and God set them in the firmament of the heavens” (Gen. 1:17); that is, according to the view of him who regards this as spoken with reference to the spheres. The learned Rabbi Abraham ben Ezra has expounded the firmament as meaning “the air.””

“In relation to unity, there are two testaments, the one giving birth into slavery and, the other, into freedom; the one of fear and the other of love, the one literal and the other spiritual, the one figurative and the other actual: and so these two times are distinguished as are the night and the day. Hence, in the Psalm: "Day pours out the word to day, and night to night imparts knowledge." During that night, the Law was like the moon, and according to Gregory the Fathers were like the stars. But when the Sun came, the day was light.”

“"Day." Here he excludes the impediment to teaching, and he excludes a threefold impediment. Sometimes teaching is impeded so that it cannot be learned because of time; sometimes because of the variety of languages; sometimes because of diversity of places. The first impediment concerns nighttime, for it is not a time for reading, since it is a time for resting; and according to different times it is fitting to teach and to learn. And first we must speak of material days that are caused according to nature from the motion of the heavens. And therefore it is necessary to consider not only the substance of the heavens but also the motion of the firmament; and thus wisdom must be understood in this alternation: Eccl. 33: "Why does one day surpass another day, and one light another light, and one year another year, from the sun? By the knowledge of the Lord they were distinguished," that is, disposed above. And therefore he says, "Day," succeeding, "to day utters speech," that is, the day of wisdom, that is, it manifests the order and goodness of divine wisdom, insofar as one day is greater than another, and so on. On one day the heat is greater than on another, and so with each. "And night." Above he showed divine wisdom and the order of divine disposition, because night succeeds night in an ordered way. And he says that day "utters," because the time of day is the time of speaking; and therefore it is the time of the word. For this reason he says, "utters speech." But nighttime is the time of meditation, because of quiet; and therefore in the quiet of the night a man meditates and discovers many things by which he becomes knowledgeable; and therefore it is the time of knowledge. And therefore he says, "And night," succeeding, "to night declares knowledge," that is, of God; because in one night there is a different disposition of time than in another; and all of this comes from the knowledge of God who disposes it. According to the truth, the apostles are called days. And this is what he says: "Day," that is, the apostles, "utters speech" of divine wisdom "to day," that is, to the perfect: 1 Cor. 2: "We speak wisdom among the perfect"; for not all things are preached to all, but clear things to the clear, holy things to the holy, great things to the great. Likewise the apostle, insofar as he is night, that is, living in the flesh and mortal, condescending to the weakness and ignorance of the unlearned, as night "declares knowledge to night," that is, to the perfect, but about human things: 1 Cor. 3: "I could not speak to you as to spiritual persons, but as to carnal. As little ones in Christ, I gave you milk to drink, not solid food." Or "day," that is, Gabriel, "utters speech to day," that is, proposes the word of the Savior to the Blessed Virgin; but "night," that is, the Devil, "declares knowledge to night," that is, to Eve: Gen. 3: "You shall be as gods, knowing good and evil."”