Furnish thyself with arguments from the promises to enforce thy prayers, and make them prevalent with God. The promises are the ground of faith, and faith, when strengthened, will make thee fervent, and such fervency ever speeds and returns with victory out of the field of prayer. The mightier any is in the Word, the more mighty he will be in prayer.

The Christian in Complete Armour (ed. Banner of Truth, 1979)