The Gate Of Gnosis

Meditation is the gate of gnosis--though the servant were to serve God with outward acts of devotion for a thousand years and a thousand years again and then were not acquainted with the practice of meditation, all his service would but increase his distance from God and increase the hardness of his heart and diminish his faith. Meditation is the chief possession of the gnostic, that whereby the sincere and the God-fearing make progress on the journey to God; it brings comfort to the sorrowing and rest to those who have renounced all for his sake. It is a strength to the godly and a means of exaltation to the devout.

~ al-Muhasibi (9th century CE), tr. Margaret Smith.