Texts Explained; Eleventhly, Mark 13:32 and Luke 2:52 Arianexplanation of the former text is against the Regula Fidei; and against the context. Our Lord said He was ignorant of the Day, by reason of His human nature. If the Holy Spiritknowsthe Day, therefore the Son knows; if the Son knowsthe Father, therefore He knowsthe Day; if He has all that is the Father's, therefore knowledge of the Day; if in the Father, He knowsthe Day in the Father; if He created and upholds all things, He knowswhen they will cease to be. He knowsnot as Man, argued from Matthew 24:42. As He asked about Lazarus's grave, etc., yet knew, so He knows; as St. Paul says, 'whether in the body I knownot,' etc., yet knew, so He knows. He said He knew not for our profit, that we be not curious as in Acts 1:7 , where on the contrary He did not say He knew not . As the Almighty asks of Adam and of Cain, yet knew, so the Son knows[as God]. Again, He advanced in wisdom also as man, else He made Angels perfect before Himself. He advanced, in that the Godhead was manifested in Him more fully as time went on
45 But for them, when they thus blaspheme the Spirit, they must expect no remission ever of such irreligion, as the Lord has said; but let us, who love Christ and bear Christ within us, know that the Word, not as ignorant, considered as Word, has said 'I know not,' for He knows, but as showing His manhood, in that to be ignorant is proper to man, and that He had put on flesh that was ignorant, being in which, He said according to the flesh, 'I know not.' And for this reason, after saying, 'No not the Son knows,' and mentioning the ignorance of the men in Noah's day, immediately He added, 'Watch therefore, for you know not in what hour your Lord does come,' and again, 'In such an hour as you think not, the Son of man comes.' For I too, having become as you for you, said 'no, not the Son.' For, had He been ignorant divinely, He must have said, 'Watch therefore, for I know not,' and, 'In an hour when I think not;' but in fact this has He not said; but by saying 'You know not' and 'When ye think not,' He has signified that it belongs to man to be ignorant; for whose sake He too having a flesh like theirs and having become man, said 'No, not the Son knows,' for He knew not in flesh, though knowing as Word. And again the example from Noah exposes the shamelessness of Christ's enemies; for there too He said not, 'I knew not,' but 'They knew not until the flood came.' For men did not know, but He who brought the flood (and it was the Saviour Himself) knew the day and the hour in which He opened the cataracts of heaven and broke up the great deep, and said to Noah, 'Come thou and all your house into the ark.' For were He ignorant, He had not foretold to Noah, 'Yet seven days and I will bring a flood upon the earth.' But if in describing the day He makes use of the parallel of Noah's time, and He did know the day of the flood, therefore He knows also the day of His own coming.
46. Moreover, after narrating the parable of the Virgins, again He shows more clearly who they are who are ignorant of the day and the hour, saying, 'Watch therefore, for you know neither the day nor the hour.' He who said shortly before, 'No one knows, no not the Son,' now says not 'I know not,' but 'ye know not.' In like manner then, when His disciples asked about the end, suitably said He then, 'no, nor the Son,' according to the flesh because of the body; that He might show that, as man, He knows not; for ignorance is proper to man. If however He is the Word, if it is He who is to come, He to be Judge, He to be the Bridegroom, He knows when and in what hour He comes, and when He is to say, 'Awake, you that sleepest, and arise from the dead, and Christ shall give you light.' For as, on becoming man, He hungers and thirsts and suffers with men, so with men as man He knows not; though divinely, being in the Father Word and Wisdom, He knows, and there is nothing which He knows not. In like manner also about Lazarus He asks humanly, who was on His way to raise him, and knew whence He should recall Lazarus's soul; and it was a greater thing to know where the soul was, than to know where the body lay; but He asked humanly, that He might raise divinely. So too He asks of the disciples, on coming into the parts of Cæsarea, though knowing even before Peter made answer. For if the Father revealed to Peter the answer to the Lord's question, it is plain that through the Son was the revelation, for 'No one knows the Son,' says He, 'save the Father, neither the Father save the Son, and he to whomsoever the Son will reveal Him.' But if through the Son is revealed the knowledge both of the Father and the Son, there is no room for doubting that the Lord who asked, having first revealed it to Peter from the Father, next asked humanly; in order to show, that asking after the flesh, He knew divinely what Peter was about to say. The Son then knew, as knowing all things, and knowing His own Father, than which knowledge nothing can be greater or more perfect.
47. This is sufficient to confute them; but to show still further that they are hostile to the truth and Christ's enemies, I could wish to ask them a question. The Apostle in the Second Epistle to the Corinthians writes, 'I knew a man in Christ, above fourteen years ago, whether in the body I do not know, or whether out of the body I do not know; God knows. ' What now say ye? Knew the Apostle what had happened to him in the vision, though he says 'I know not,' or knew he not? If he knew not, see to it, lest, being familiar with error, you err in the trespass of the Phrygians, who say that the Prophets and the other ministers of the Word know neither what they do nor concerning what they announce. But if he knew when he said 'I know not,' for he had Christ within him revealing to him all things, is not the heart of God's enemies indeed perverted and 'self-condemned?' for when the Apostle says, 'I know not,' they say that he knows; but when the Lord says, 'I know not,' they say that He does not know. For if since Christ was within him, Paul knew that of which he says, 'I know not,' does not much more Christ Himself know, though He say, 'I know not?' The Apostle then, the Lord revealing it to him, knew what happened to him; for on this account he says, 'I knew a man in Christ.' and knowing the man, he knew also how the man was caught away. Thus Elisha, who beheld Elijah, knew also how he was taken up; but though knowing, yet when the sons of the Prophets thought that Elijah was cast upon one of the mountains by the Spirit, he knowing from the first what he had seen, tried to persuade them; but when they urged it, he was silent, and suffered them to go after him. Did he then not know, because he was silent? He knew indeed, but as if not knowing, he suffered them, that they being convinced, might no more doubt about the taking up of Elijah. Therefore much more Paul, himself being the person caught away, knew also how he was caught; for Elijah knew; and had any one asked, he would have said how. And yet Paul says 'I know not,' for these two reasons, as I think at least; one, as he has said himself, lest because of the abundance of the revelations any one should think of him beyond what he saw; the other, because, our Saviour having said 'I know not,' it became him also to say 'I know not,' lest the servant should appear above his Lord, and the disciple above his Master.
Source: Four Discourses Against the Arians (New Advent)