This is a treatise we have written concerning humility (Khushu') and the hearts meekness and breaking (inkisar) before the Lord. The basic meaning of Khushu', is the softness of the heart, its being gentle, still, submissive, broken, and yearning. When the heart is humble, so too is the hearing, seeing, heard, and face; indeed all the limbs and their actions are humbled, even speech. This is why the Prophet (saw) would say in his bowing (ruku), "My hearing, sight, bones, and marrow are humbled to You," another narration has, "and whatever my foot carries." One of the Salaf saw a man fidgeting in his prayer and remarked, 'If the heart of this person was humble, so too would his limbs be.' The source of the Khushu, that takes place in the heart is the gnosis of Allah's greatness, magnificence, and perfection. The more gnosis a person has of Allah, the more Khushu' he has. The greatest action of worship which manifests the Khushu, of the body to Allah is the prayer (Salaah). Allah has praised those who have Khushu' in the prayer