B.B. Warfield, “Faith and Life” (found in Selected Shorter Writings, vol. 1.):
Convictions are the root on which the tree of vital Christianity grows. No convictions, no Christianity. Scanty convictions, hunger-bitten Christianity. Profound convictions, solid and substantial religion. Let no man fancy it can be otherwise. Ignorance is not the mother of religion, but of irreligion. The knowledge of God is eternal life, and to know God means that we know him aright.