Those who study the life of Robert Murray McCheyne know him to be a man mighty in prayer.
From E.M. Bounds collection on prayer, page 467, McCheyne addresses the topic of “The Divine Channel of Power.”
Study universal holiness of life. Your whole usefulness depends on this, for your sermons last only an hour or two; your life preaches all week. If Satan can make you a covetous minister, a lover of praise, of pleasure, or good eating, he has ruined your ministry. Give yourself to prayer, and get your texts, your thoughts, your words from God. Luther spent his best three hours in prayer.
–Robert Murray McCheyne