1 Corinthians 15:2
By which also you are saved, if you keep in memory what I preached to you, unless you have believed in vain.
If you have learned to look under your feet every day while young, and to cull the treasures of truth which belong to geology, natural history, and chemistry; if every fly has furnished you a study; if the incrustation of the frost is a matter, of interest; if the trees that come in spring, and the birds that populate them, the flowers of the meadow, the grass of the field, the fishes that disport themselves in the water — if all these are to you so many souvenirs of the working hand of your God, you will find, when you come into old age, that you have great stores of enjoyment therein. Let me therefore recommend you to commit much to memory. When a man is blind his memory is not blind. I have seen many a man who in youth had committed much to memory from the Scriptures and hymns and poems, who was able, in old age, to recall and recite what he had learned, and to fall back upon those treasures, his own head having thus become to him a library. Oh, how much a man may store up against old age! What a price is put into the hands of the young wherewith to get wisdom! What provisions for old age do they squander and throw away! It is not merely that you may be keen and strong now; it is not for the poor ambition of being esteemed learned that I urge you now to lay such treasures up; but because it is just and right and noble that you should be intelligent, and because your whole life is interested in it, and your old age pre-eminently so.
(H. W. Beecher.)
Parallel VersesKJV: By which also ye are saved, if ye keep in memory what I preached unto you, unless ye have believed in vain.