John Chrysostom, on 1Cor 15:8

"And last of all he appeared unto me also, as unto one born out of due time."

This is rather an expression of modesty than any thing else. For not because he was the least, therefore did he appear to him after the rest. Since even if He did call him last, yet he appeared more illustrious than many which were before him, yea rather than all. And the five hundred brethren too were not surely better than James, because He appeared to them before him.

Why did He not appear to all at the same time? That He might first sow the seeds of faith. For he that saw Him first and was exactly and fully assured, told it unto the residue: then their report coming first placed the hearer in expectation of this great wonder, and made way before for the faith of sight. Therefore neither did He appear to all together, nor in the beginning to many, but to one alone first, and him the leader of the whole company and the most faithful: since indeed there was great need of a most faithful soul to be first to receive this sight. For those who saw him after others had seen him, and heard it from them, had in their testimony what contributed in no small degree to their own faith and tended to prepare their mind beforehand; but he who was first counted worthy to see Him, had need, as I have said, of great faith, not to be confounded by a sight so contrary to expectation. Therefore he appears to Peter first. For he that first confessed Him to be Christ was justly also counted worthy first to behold His resurrection. And not on this account alone doth He appear to him first, but also because he had denied Him, more abundantly to comfort him and to signify that he is not despaired of, before the rest He vouchsafed him even this sight and to him first entrusted His sheep. Therefore also He appeared to the women first. Because this sex was made inferior, therefore both in His birth and in His resurrection this first tastes of His grace.

But after Peter, He appears also to each at intervals, and at one time to fewer, at another to more, hereby making them witnesses and teachers of each other, and rendering His apostles trustworthy in all that they said.

What mean here his expressions of humility, or wherein are they seasonable? For if he wishes to show himself worthy of credit and to enrol himself among the witnesses of the resurrection, he is doing the contrary of what he wishes: since it were meet that he exalt himself and show that he was great, which in many places he doth, the occasion calling for it. Well, the very reason why he here also speaks modestly is his being about to do this. Not straightway, however, but with his own peculiar good sense: in that having first spoken modestly and heaped up against himself many charges, he then magnifies the things concerning himself. What may the reason be? That, when he comes to utter that great and lofty expression concerning himself, "I labored more abundantly than all," his discourse may be rendered more acceptable, both hereby, and by its being spoken as a consequence of what went before and not as a leading topic. Therefore also writing to Timothy, and intending to say great things concerning himself, he first sets down his charges against himself. For so all persons, when speaking in high terms of others, speak out freely and with boldness: but he that is compelled to praise himself, and especially when he also calls himself to witness, is disconcerted and blushes. Therefore also this blessed man first declares his own misery, and then utters that lofty expression. This then he doth, partly to abate the offensiveness of speaking about himself, and partly that he might hereby recommend to their belief what he had to say afterwards. For he that truly states what things are discreditable to him and conceals none of them, such as that he persecuted the Church, that he laid waste the faith, doth hereby cause the things that are honorable to him also to be above suspicion.

And consider the exceeding greatness of his humility. For having said, "and last of all He appeared to me also," he was not content with this: "For many that are last shall be first," saith He, "and the first last." Therefore he added, "as unto one born out of due time." Neither did he stop here, but adds also his own judgment and with a reason.

But consider how he abounds in the expressions of humility. For so, "to me last of all He appeared," saith he. Wherefore neither doth he with himself mention any other, and saith, "as of one born out of due time," and that himself is "the least of the apostles," and not even worthy of this appellation. And he was not content even with these, but that he might not seem in mere words to be humble-minded, he states both reasons and proofs: of his being "one born out of due time," his seeing Jesus last; and of his being unworthy even of the name of an apostle, "his persecuting the Church." For he that is simply humble-minded doeth not this: but he that also sets down the reasons utters all from a contrite mind. Wherefore also he elsewhere makes mention of these same things, saying, "And I thank him that enabled me; even Christ Jesus our Lord, for that He counted me faithful, appointing me to his service, though I was before a blasphemer, and a persecutor, and injurious."