When we try to remember something and feel like it is just out of reach for the moment, we say it is on the tip of our tongue. The expression denotes an attempt to recall what was previously known but has slipped from our conscious memory.
I believe that much of our human struggle to comprehend the divine is a process of recalling as opposed to learning in the first place. The answers we seek are already inside and seeking them externally simply misdirects the search process. Real understanding is an intuitive exercise which means it can't be poured into us by someone else. The thoughts of others can be helpful but not conclusive.
Divine knowledge a is always on the tip of the tongue, yours and not someone else's. Let your heart recall what you need to know.