Martin Luther
The god of this world is riches, pleasure and pride.

If we forget that it is God’s prerogative to give results when the gospel is preached, we shall start to think that it is our responsibility to secure them. And if we forget that only God can give faith, we shall start to think that the making of converts depends, in the final analysis, not on God, but on us, and that the decisive factor is the way we evangelize. This line of thought consistently followed out will lead us astray.
J.I. Packer