1. Answers to prayer gives us proof of His existence. Says E. M. Bounds, “There is no proof so clear and demonstrative that God exists than prayer and its answers.”
2. Answers to prayer gives us confidence that we have a right relationship with Him and that He is pleased with us and with our prayers. Again E. M. Bounds states, “Answer to prayer is the convincing proof of our right relations to God.”
E. M. Bounds, The Possibilities of Prayer (Baker Book House: Grand Rapids, Michigan) 1979, p. 86-87.