Grudem on Prayer

Grudem, Wayne A, Systematic Theology: Introduction to Bible Doctrine (Grand Rapids, MI: Zondervan, 1994), 377.

James tells us, “You do not have, because you do not ask” (James 4:2). He implies that failure to ask deprives us of what God would otherwise have given to us

If we were really convinced that prayer changes the way God acts, and that God does bring about remarkable changes in the world in response to prayer, as Scripture repeatedly teaches that he does, then we would pray much more than we do. If we pray little, it is probably because we do not really believe that prayer accomplishes much at all.