Classic Essays on Prayer

"The whole work of faith in obedience is denominated from this duty of prayer, for so it is said that 'whosoever shall call upon the name of the Lord shall be saved,' Romans 10:13; for invocation or prayer, in the power of the Spirit of grace and supplication, is an infallible evidence and fruit of saving faith and obedience, and therefore is the promise of salvation so eminently annexed unto it, or it is placed by a synecdoche for the whole worship of God and obedience of faith. And it were endless to declare the benefits that the church of God, and every one that belongeth thereunto, hath thereby. No heart can conceive that treasury of mercies which lies in this one privilege, in having liberty and ability to approach unto God at all times, according unto his mind and will. This is the relief, the refuge, the weapons, and assured refreshment, of the church in all conditions." (John Owen, 'A Discourse of the Work of the Holy Spirit in Prayer')