The most powerful prayer, one well nigh omnipotent, and the worthiest work of all is the outcome of a quiet mind. The quieter the mind, the more powerful, the worthier, the deeper, the more telling and more perfect the prayer is. To the quiet mind all things are possible. What is a quiet mind? A quiet mind is one which nothing weighs on, nothing worries, which, free from ties and from all self-seeking, is wholly merged into the will of God and dead to its own. Such a one can do no deed, however small, that is not clothed with something of God’s power and authority. It behooves us to pray hard so that all our mortal members with their powers—eyes, ears, heart, mouth, and all their senses—are turned in that direction, and we must never stop until we find ourselves on the point of union with him we have in mind and are praying to, namely God.
Eckhart, Meister; O’Neal, David (2012-09-10). Meister Eckhart, from Whom God Hid Nothing: Sermons, Writings, & Sayings (Kindle Locations 355-361). Shambhala Publications. Kindle Edition.