The Prophet said, “Go ahead and call for prayer”, then taught him the words of the athan, then mentioned, “May God bless you.” As a result, God guided Aba Mahthoora to Islam and he became the “muathan (the one who calls to prayer) of the Prophet in Mecca. This is the story of how Aba Mahthoora started as a disbeliever, who made fun and mockery of the athan, but ended as a truthful believer and the Muathan of the Prophet, may the mercy and blessings of God be upon him. (Musnad Ahmad # 15380).