Satan cannot deny but that great wonders have been wrought by prayer. As the spirit of prayer goes up, so his kingdom goes down. Satan's strategems against prayer are three. First, if he can, he will keep thee from prayer. If that be not feasible, secondly, he will strive to interrupt thee in prayer. And, thirdly, if that plot takes not, he will labour to hinder the success of thy prayer.
William GurnallFurnish 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.
William Gurnall