The sentence is
"The point of interest was to determine how far the natural light of reason, human reason by itself, could progress in the knowledge of truth, with the important proviso that through religion humans could learn higher truths than reason is in a position to discover from itself?"
Could you please help me clarify this sentence as well? Plus, does that sound like well translated from German? I think it is very complicated and the elements of the sentence are all over the place.