Musannaf Ibn Abi Shaybah 7338 — Those who said: follow the imam

Sayyiduna al-Bara bin Azib (may Allah be pleased with him) said: We used to pray behind the Prophet (peace and blessings be upon him). After rising from bowing we would remain standing in rows until, when he (peace and blessings be upon him) prostrated, we too prostrated following him.