Majma al-Zawaid 2629 — Bismillah al-Rahman al-Rahim

Ibrahim al-Sa'igh narrates: I asked Matar al-Warraq, saying: "Do you recite 'Bismillahir-Rahmanir-Rahim' and 'A'udhu billahi minash-shaytanir-rajim' in every rak'ah and at the beginning of every surah?" He replied: Qatadah narrated to me, from Muhammad bin Sirin, from Sayyiduna Imran bin Husayn (may Allah be pleased with him) and Samurah bin Jundub (may Allah be pleased with him), this saying of the Prophet (peace and blessings be upon him): "These are two pauses which a person observes within himself: when he begins the prayer, and when he rises from the sitting after two rak'ahs."
Al-Tabarani recorded it in al-Mu'jam al-Kabir. Its chain contains a narrator Rayhan Abu Ghassan, whom I do not know; the remaining narrators of this report are "thiqat" (trustworthy).