A hadith similar to this is narrated from Sayyiduna Abdullah bin Zaid (may Allah be pleased with him) through another chain, and in it, there is further mention of this matter. Then the Prophet (peace and blessings be upon him) ordered the call to prayer (adhan) to be given. Sayyiduna Bilal (may Allah be pleased with him), the freed slave of Sayyiduna Abu Bakr Siddiq (may Allah be pleased with him), used to call the adhan with these same words and would call the Messenger of Allah (peace and blessings be upon him) for prayer. Sayyiduna Abdullah bin Zaid says: One day, Bilal (may Allah be pleased with him) went to call you for the Fajr prayer in the morning, and he was told that the Messenger of Allah (peace and blessings be upon him) was sleeping, so Bilal (may Allah be pleased with him) loudly proclaimed: "As-salatu khayrun minan-nawm" (Prayer is better than sleep). Sa'id bin al-Musayyib says: So these words were included in the adhan for Fajr. (1267)