Isa 7:15

“(Verse 15) He shall eat butter and honey, so that he may know how to refuse the evil and choose the good. For before he knows to refuse the evil and choose the good, the land that you dread will be forsaken by both her kings. The Lord will bring the king of Assyria upon you and your people and your father's house—days that have not come since the day that Ephraim departed from Judah. And it shall come to pass in that day, that the Lord shall hiss for the fly that is in the uttermost part of the rivers of Egypt, and for the bee that is in the land of Assyria. And they shall come, and shall rest all of them in the desolate valleys, and in the holes of the rocks, and upon all thorns, and upon all bushes. I will say something even more amazing, so that you do not think that he is born in a fantasy, he will use foods of infancy, he will eat butter and milk. And although many centuries later the Evangelist testifies about him: But the child grew in wisdom and age and grace before God and men (Luke 2:52): and this is said to confirm the truth of the human body: yet still wrapped in swaddling clothes, and fed with butter and honey, he will have the ability to judge between good and evil, so that he may reject evil and choose good. Not because he did or disapproved or chose this, but because he knew how to disapprove and choose, so that through these words we may know that the infancy of the human body did not hinder divine wisdom. Lastly, the Angels announce to the shepherds the laying in the manger: The Magi adore coming from the East, whom it is to be believed were certainly chosen. And on the other hand, Herod, the scribes, and the Pharisees are disapproved, (Matthew 2), because they killed many thousands of infants for the sake of one child.”

“This is said ["The child grew in wisdom and in age before God and men"] in order to establish the truth of his human body. Nevertheless, wrapped in swaddling clothes and fed with curds and honey, he will have the judgment to distinguish between good and evil, that rejecting evil he might choose the good. It does not say that he will in fact reject and choose but that he would learn to reject and to choose, so that we might know through such words that this pertains to the infant's human body, not to divine wisdom. Finally, it must be believed that the angels who announced to shepherds the news of the infant lying in a manger and the magi who came from the east to worship him were chosen. Herod, the scribes and the Pharisees, on the other hand, were condemned because they slaughtered thousands of children for the sake of one infant.”

“Now, since the Lord was not a mere man but was also God and knew all things, he stood in no need of reflection, inquiry, counsel or judgment. He also had a natural affinity for good and antipathy for evil. Thus it is in this sense that the prophet Isaiah, too, says, "Before the child shall know to refuse the evil, he will choose the good. For before the child knows to refuse the evil and to choose the good, he will reject the evil by choosing the good." The "before" shows that he made no inquiry or investigation in a human manner but that since he was God and divinely subsisted in the flesh—that is to say, was personally united to the flesh—by the fact of his very being and his knowing all things he naturally possessed the good.”

“Cream and honey he shall eat [i.e.,] the child [shall eat,] for our land shall be replete with all good. when he knows to reject bad and choose good Heb. לְדַעְתּוֹ [lit. to his knowledge], when he knows to reject bad and choose good. Now whence will we have this plenty? Is not our land desolate now from the troops of the kings of Aram and Pekah the son of Remaliah?”

“ברע The bad. The bad food; as הטוב the good means the good food.”

“Second, as to his humanity: he shall eat butter and honey, literally, manly foods, because from infancy he held himself to the manner of other men: and being born, I drew in the common air, and fell upon the earth, that is made alike, and the first voice which I uttered was crying, as all others do (Wis 7:3). Or from the part to the whole, according to the rules of Tyconius: for through these he understands all human foods. That he may know. The "that" is consecutive, for, feeding on such things, the child still knows to refuse the evil, without experience, and to choose the good, without counsel, having all perfect knowledge. The devil had promised this, but did not fulfill it (Gen 3:5); but God gave it freely: for he has given me the true knowledge of the things that are: to know the disposition of the whole world, and the virtues of the elements (Wis 7:17). Or, "that" is causal: that he may know, that is, that he may show himself to know, because he is led through the foods to the perfect quantity of years, in which he shows himself to know. Augustine on Song of Songs 4:11, honey and milk, says that humanity is signified by butter, because it comes from the nourishment of the earth; divinity is signified by honey, because it is collected from the dew of heaven. He had, moreover, a nature without corruption, like butter without curd; and he carried consolation without judgment, like honey without the sting. Bernard: our little one chose to be newly conceived, because he took the nature of our flesh without corruption. Similarly, the bee brings us honey without mingling in the sting. He came not to judge the world, but that the world may be saved by him (John 3:17). And thus, "that" is also causal. And this is a sign from below on the part of the virgin giving birth, and from above on the part of God being born: the Lord will give goodness: and our earth shall yield her fruit (Ps 84:13[85:12]).”