"The meaning and the purpose of human existence become clear when we present ourselves to God as a pure and holy sacrifice. For what reason, in fact, did God give us the gift of life and of existence if not so that we would have something precious to offer Him, which we could return to him as gift?"
In some ways that's a foreign idea to me since I mostly think of being on the receiving end rather than the giving.
Humility is the key to everything because faith precedes understanding and that takes humility, to admit we don't have all the answers and can't get to some answers through human effort. Came across another beautiful quote in the book of Wisdom. "For neither herb nor moulding plaster cured them / but it was your word, Oh Lord, that heals all people." A rather startling rebuke to the idea that "in Science (or medicine) we trust."