Abū Dāwūd and Aḥmad, with an authentic chain, reported that he said to "the one who performed his prayer incorrectly": "when you prostrate, make your prostration firm" (Ibn Khuzaymah with a good chain). In another narration: "when you prostrate, ensure your face and hands are firmly placed until each bone of yours settles in its place" (al-Dāraqūṭnī and al-Ṭabarānī). He used to say: "There is no prayer for the one whose nose does not touch the ground as the forehead does" (authentic). and he would also firmly place his knees and the tips of his feet. and he would face the qiblah with the soles [of his feet and] the tips of his toes. and he would keep his heels together. and he would raise his feet and commanded this. He would spread their toes apart. These are the seven parts on which he (ṣallá Allāhu ʿalayhi wa-sallam) would prostrate: the palms, the knees, the feet, the forehead, and the nose