Sayyiduna Jabir bin Samurah (may Allah be pleased with him) narrates: We used to perform prayer behind the Prophet Muhammad (peace and blessings be upon him). When any one of us finished the prayer with salam, he would gesture with his hand to the right and to the left, saying: "As-salamu alaikum, as-salamu alaikum." So the Prophet Muhammad (peace and blessings be upon him) said: "What is the matter that you move your hands like the tails of unruly horses? Is it not sufficient for you that a man places his hand on his knees and then greets his brother on his right and greets his brother on his left by saying: 'As-salamu alaikum wa rahmatullah, as-salamu alaikum wa rahmatullah'?"