We must not limit God's knowledge because we cannot grasp how he knows; it is safer to err on the side of his knowing
We certainly ought not to presume so much on ourselves as to dare to set limits to God's knowledge and deny that he knows something because we cannot understand how he would know it. God's intellect, infinite in every way, doubtless knows more than we can grasp or reach.
At any rate, someone who thinks God knows things that perhaps are not knowable errs less dangerously than someone who denies that God knows what he really does know, things that fall within the object of his omniscience.
Latin
LXIV. Sed certe tantum de nobis praesumere non debemus, ut divinam scientiam limitare ausimus, & negare quod Deus aliquid sciat, quia quomodo sciret comprehendere non valemus. Nam divinus intellectus omnimodo infinitus plus scit proculdubio quam valeamus capere & assequi. Saltem ille minus periculose errat, qui putat Deum scire ea quae forte scibilia non sunt; quam qui negat Deum scire quae revera scit, & quae intra divinae omniscientiae objectum continentur.