Clement of Alexandria : Philosophers, then, are children, unless they have been made men by Christ. "For if the son of the bond woman shall not be heir with the son of the free," at least he is the seed of Abraham, though not of promise, receiving what belongs to him by free gift. "But strong meat belongeth to those that are of full age, even those who by reason of use have their senses exercised to discern both good and evil." "For every one that useth milk is unskilful in the word of righteousness; for he is a babe," and not yet acquainted with the word, according to which he has believed and works, and not able to give a reason in himself. "Prove all things," the apostle says, "and hold fast that which is good," speaking to spiritual men, who judge what is said according to truth, whether it seems or truly holds by the truth. — The Stromata Book 1 Ephrem the Syrian : "Every one who lives on milk" as food … whose hope of salvation is in the promises of the earthly law, is "unskilled in the word of righteousness," that is, in the crucifixion of our flesh, by which the righteousness of God is proclaimed. — COMMENTARY ON THE EPISTLE TO THE Hebrews 5 John Chrysostom : "For every one that partaketh of milk is unskilled in the word of righteousness: for he is a babe." What is "the Word of righteousness"? He seems to me here to hint at conduct also. That which Christ also said, "Except your righteousness shall exceed the righteousness of the Scribes and Pharisees", this he says likewise, "unskilled in the word of righteousness," that is, he that is unskilled in the philosophy that is above, is unable to embrace a perfect and exact life. Or else by "righteousness" he here means Christ, and the high doctrine concerning Him. That they then were "become dull," he said; but from what cause, he did not add, leaving it to themselves to know it, and not wishing to make his discourse hard to bear. But in the case of the Galatians he both "marveled" and "stood in doubt", which tends much more to encourage, as it is the language of one who would never have expected that this should happen. For this is what the doubting implies. Thou seest that there is another infancy, Thou seest that there is another full age. Let us become of "full age" in this sense: It is in the power even of those who are children, and the young to come to that "full age": for it is not of nature, but of virtue. — Homily on Hebrews 8 Oecumenius : To those who are still infants, faith is seen in humble words, (for milk is suitable for infants), but to the perfect, faith is in solid food and the high thinking concerning Christ. "For everyone who lives on milk." For everyone, he says, who partakes of humble words, concerning the humanity of the Lord, (for these are the milk), is unskilled and lacks the word of righteousness. — The Pseudo-Oecumenian Catena on Hebrews