Maqalat al-Islamiyyin

Maqalat al-Islamiyyin wa Ikhtilaf al-Musallin (Arabic: مقالات الإسلاميين واختلاف المصلين, lit. 'The Treatises/Teachings of the Muslims and the Differences of the Prayerful/Worshippers') is one of the main heresiographical works of early Islamic sects written by the Sunni scholar Abu al-Hasan al-Ash'ari (d. 324/935), the eponym of the Ash'ari theological school.

Most likely, al-Ash'ari wrote this book following the Mu'tazili theologian Abu al-Qasim al-Balkhi (d. 319/931) in his book with the same title (Maqalat al-Islamiyyin). Therefore, it was probably written during his Mu'tazili period and then modified; thus it may incorporate parts which he wrote earlier when he was still a Mu'tazili. However, according to al-Dhahabi (d.748/1348), this book was written in his last years, which indicates tolerance with Islamic sects, because Islam contains them.