Musannaf Ibn Abi Shaybah 3567 — Straightening the row

Hittan bin Abdullah al-Raqashi said: Sayyiduna Abu Musa al-Ash'ari (may Allah be pleased with him) led us in prayer. When he finished the prayer, he said: The Prophet (peace and blessings be upon him) addressed us, explained our religion to us and taught us how to pray. In that address he said: "When you pray, straighten your rows."