Ambrose of Milan : Nor does everyone undertake this business matter, but only the sons of Jacob and only those sons of more mature age. Thus ten sons go, whereas the youngest son does not go. The father did not send him; else "infirmity may befall him." Benjamin, the youngest, was still subject to infirmity. Granted, [in] the name Benjamin the patriarch is read, but Paul, who was of the tribe of Benjamin, was being prefigured. Jacob was right to hesitate over his infirmity. Indeed, he was made infirm so that he could be healed. Paul suffered blindness, but this was an infirmity unto salvation.Yes, that blindness brought Paul light. We have received the story; let us come to know the mystery. The patriarchs had gone at first without Benjamin, as the apostles first went without Paul. Each came, not as the first, but was summoned by those who were the first, and by his arrival he made the goods of those who were first more plenteous. — On Joseph the Patriarch