Sayyiduna Abdullah bin Umar (may Allah be pleased with them) narrates that when the Muslims (after migrating) reached Madinah, they would come for prayer at the appointed time, but no adhan was given for it. One day, there was a consultation about this matter. Someone suggested adopting a bell like the Christians, and someone else said to make a horn (bugle) like the Jews and blow it. But Sayyiduna Umar (may Allah be pleased with him) said, "Why not send someone who would call out for the prayer?" Upon this, the Messenger of Allah (peace and blessings be upon him) (approved of this opinion and said to Sayyiduna Bilal, may Allah be pleased with him), "Bilal, get up and give the adhan for the prayer."