16 As yet that Israel perchance does not understand what are the holocausts thereof which He has in His sight always, and is still thinking of oxen, of sheep, of he-goats: let it not so think: “I will not accept calves of your house.” Holocausts I named; at once in mind and thought to earthly flocks you were running, therefrom you were selecting for Me some fat thing: “I will not accept calves of your house.” He is foretelling the New Testament, wherein all those sacrifices have ceased. For they were then foretelling a certain Sacrifice which was to be, with the Blood whereof we should be cleansed. “I will not accept calves of your house, nor he-goats of your flocks.”
17. “For mine are all the beasts of the wood”. Why should I ask of you what I have made? Is it more yours, to whom I have given it to possess, than Mine, who have made it? “For mine are all the beasts of the wood.” But perchance that Israel says, The beasts are God's, those wild beasts which I enclose not in my pen, which I bind not to my stall; but this ox and sheep and he-goat— these are my own. “Cattle on the mountain, and oxen.” Mine are those which you possess not, Mine are these which you possess. For if you are My servant, the whole of your property is Mine. For it cannot be, that is the property of the master which the servant has gotten to himself, and yet that not be the property of the Master which the Master Himself has created for the servant. Therefore Mine are the beasts of the wood which you have not taken; Mine are also the cattle on the mountains which are yours, and the oxen which are at your stall: all are My own, for I have created them.
18. “I know all the winged creatures of heaven”. How does He know? He has weighed them, has counted. Which of us knows all the winged creatures of heaven? But even though to some man God give knowledge of all the winged creatures of heaven, He does not Himself know in the same manner as He gives man to know. One thing is God's knowledge, another man's: in like manner as there is one possession of God's, another of man's: that is, God's possessing is one thing, man's another. For what you possess you have not wholly in your power, or else your ox, so long as it lives, is in your power; so as that it either die not, or be not to be fed. With whom there is the highest power, there is highest and most secret cognition. Let us ascribe this to God, while praising God. Let us not dare to say, How knows God? Do not, I pray you, brethren, of me expect this, that I should unfold to you, how God does know: this only I say, He does not so know as a man, He does not so know as an Angel: and how He knows I dare not say, because also I cannot ken. One thing, nevertheless, I ken, that even before all the winged creatures of heaven were, God knew that which He was to create. What is that knowledge? O man, you begin to see, after that you had been formed, after that you had received sense of seeing. These fowls sprung of the water at the word of God, saying, “Let the waters bring forth fowls.” Whereby did God know the things which He commanded the water to bear forth? Now surely He knew what He had created, and before He created He knew. So great then is the knowledge of God, so that with Himself they were in a certain ineffable manner before they were created: and of you does He expect to receive what He had, before He created? “I know all the winged creatures of heaven,” which thou to Me canst not give. The things which you were about to slay for Me, I know all: not because I made I know, but in order that I might make. “And the beauty of the field is with Me.” The fairness of the field, the abundance of all things engendering upon earth, “is with Me,” He says. How with Him? Were they so, even before they were made? Yea, for with Him were all things to come, and with Him are all things by-gone: things to come in such sort, that there be not withdrawn from Him all things by-gone. With Him are all things by a certain cognition of the ineffable wisdom of God residing in the Word, and the Word Himself is all things. Is not the beauty of the field in a manner with Him, inasmuch as He is everywhere, and Himself has said, “Heaven and earth I fill”? What with Him is not, of whom it is said, “If I shall have ascended into heaven, You are there; and if I shall have descended into hell, You are present”? With Him is the whole: but it is not so with Him as that He does suffer any contamination from those things which He has created, or any want of them. For with you, perchance, is a pillar near which you are standing, and when you are weary, you lean against it. You need that which is with you, God needs not the field which is which Him. With Him is field, with Him beauty of earth, with Him beauty of heaven, with Him all winged creatures, because He is Himself everywhere. And wherefore are all things near Him? Because even before that all things were, or were created, to Him were known all things.
Source: The Enarrations, or Expositions, on the Psalms (New Advent)