سنن النسائي

It was narrated from Ibn 'Abbas: "The Prophet (ﷺ) was commanded to prostrate on seven-and he was forbidden to tuck up his hair and garment-on his hands, his knees, the edges of his feet." Sufyan said: "Ibn Tawus said to us: 'He put his hand on his forehead and moved it down to his nose and said: This one thing.'"