It’s a Socratic inheritance: you have knowledge=wisdom when and only when you can articulate and explain your commitments without contradicting yourself. (There’s some of this in Aristotle, too, of course.)
I think Aquinas has echoes of this too, for scientia. He wants to say faith has equal certainty to scientia, w/o those same epistemic requirements. So what do faith and knowledge have in common? He says they're "without fear of the opposite," which sounds like subjective certainty to me.