Jesus was, and is, fully God and fully man. As God, he was omniscient; as man, his experiential knowledge (i.e., knowledge that is gained through human experience) could grow through learning. St. Thomas Aquinas asserted that Christ, in his human intellect, knew all things through the beatific vision but that in his human mind -- which is a created thing and therefore finite -- he could not know all the possibilities. If this sounds mysterious, that's because it is
mysterious, not in the more limited sense of puzzling, but in the theological sense of a truth of the faith that we cannot fully comprehend.
The Human Knowledge of Christ
by John O'Connell
To Know Christ Jesus
by Frank Sheed