You are challenged to avoid ...

You are challenged to avoid mediocrity, acquire knowledge from the sages of antiquity, the achievements of the scientific present, and the prophets of the living God. Isaiah once spoke as follows, In an acceptable time have I heard thee, and in a day of salvation have I helped thee
 John H. Vandenberg

Quotes from the same author

We become what we think about most.
 John H. Vandenberg
If a man achieves worldly success and does not blend into his life a program of self-improvement to bring about a sensible balance, he no doubt will end up as a failure.
 John H. Vandenberg