Great is that which no man can take away.

Knowledge

No thief, however skillful, can rob one of knowledge, and that is why knowledge is the best and safest treasure to acquire.
— L. Frank Baum, The Lost Princess of Oz

Memories

The only real treasure is in your head. Memories are better than diamonds and nobody can steal them from you.
— Rodman Philbrick, The Last Book in the Universe

Faith

38 For I am convinced that neither death nor life, neither angels nor demons, neither the present nor the future, nor any powers, 39 neither height nor depth, nor anything else in all creation, will be able to separate us from the love of God that is in Christ Jesus our Lord.
— Romans 8:38-39