Gregory the Dialogist

Didst thou know then that thou wast about to be born, and didst thou know the number of thy days? As if He were openly saying, What wonder if thou understandest not thine end, since thou dost not comprehend thy beginning? And since thou knowest not with what beginning thou camest hither, what wonder, if thou canst not tell with what end thou art taken away? If therefore it was My work to bring thee forward from secresy to sight at thy beginning, it will be Mine also to bring thee back from sight to secresy. …

Morals on the Book of Job, Book XXIX ↗

Thomas Aquinas

The duration of the lower bodies and the times of generation and corruption are measured according to the motion of the heavenly bodies, as Dionysius says in Chapter IV of The Divine Names. Therefore, when one is ignorant of these causes, one consequently does not know the effects, and so he says, "Did you know when you were born then?" as if to say: Could you know the time of your birth in advance by considering the motion of the heavens? …

Commentary on Job ↗