Sahih Ibn Khuzaymah

Sayyiduna Abbas bin Sahl (may Allah be pleased with him) narrates that (once) Sayyiduna Abu Humayd Sa’idi, Abu Usaid Sa’idi, Sahl bin Sa’d Sa’idi, and Muhammad bin Maslamah (may Allah be pleased with them) gathered together. Then Sayyiduna Abu Humayd (may Allah be pleased with him) said, “I know the prayer of the Messenger of Allah (peace and blessings be upon him) better than all of you.” (The noble companions, may Allah be pleased with them, said, “Then please describe the prayer of the Messenger of Allah, peace and blessings be upon him.”) He said, “When the Messenger of Allah (peace and blessings be upon him) stood for prayer, he would say « اللهُ أَكْبَرُ ». Then, after narrating some of the hadith, he said, ‘Then when the Messenger of Allah (peace and blessings be upon him) performed sajdah, he would firmly place his forehead and nose on the ground, and he would keep his arms away from his sides and place his hands in line with his shoulders. Then he (peace and blessings be upon him) would raise his head until every bone returned to its place (then he, peace and blessings be upon him, would continue to pray with the same calmness and tranquility) until he (peace and blessings be upon him) finished.’”