Musannaf Ibn Abi Shaybah 3151 — A man who misses part of the prayer

Some elders of Banu Rasib said: Sayyiduna Talhah and Sayyiduna al-Zubayr (may Allah be pleased with them both) prayed in one of our mosques, and there was no imam there. So we said to them: "Let one of you step forward and lead the prayer, for you are both among the Companions of the Messenger of Allah (peace and blessings be upon him)." They both declined to lead and said: "Where is the imam? Where is the imam?" Meanwhile the imam came and led the people in prayer. When they had finished the prayer, the two of them said: "Every act of your prayer is fine, except one thing that is not good." We asked: "What is it?" They said: "When the imam gives the salam, the one following him should not stand up until the imam turns his face around or rises from his place."