根据他的传记作者记载，阿卜杜拉·马蒙从拉卡（al-Raqqah）致信巴格达警察总长伊斯哈格·伊本·易卜拉欣，命令他对民众进行考验，他便照办了。671

According to his biographers, al-Maʾmūn sent a letter from al-Raqqah 338 to the chief of the Baghdad police, Isḥāq ibn Ibrāhīm, telling him to put the community to the test, which he did. 67.1

[Ṣāliḥ:] 我听父亲说：“当他们把我们带去接受艾哈迈德·伊本·易卜拉欣的讯问时，他们首先朗读了那位在塔尔苏斯的人所写的信”——即阿卜杜拉·马蒙。“他们向我们诵读了一些经文，包括《他毫无相似》和《他是万物的创造者》。我听到‘他毫无相似’时，便诵读了《他是全听的，全见的》。”67.2

[Ṣāliḥ:] I heard my father say, “When they took us in to be questioned by Isḥāq ibn Ibrāhīm, the first thing they did was to read aloud the letter written by the one in Tarsus”—that is, al-Maʾmūn.339 “They recited some verses to us, including «Nothing is like Him»340 and «He is the creator of everything.»341 When I heard ‘Nothing is like Him,’ I recited «He is the One who hears and sees.»342 67.2

然后，在场的人都受到了考验。拒绝表示同意的人被带走并关押起来。在所有人中，只有四人坚持抵抗。他们的名字是：穆罕默德·伊本·努哈；欧拜杜拉·伊本·欧麦尔·古瓦利里；被称为萨贾达的哈桑·伊本·哈马德；以及我的父亲。后来，欧拜杜拉·伊本·欧麦尔和哈桑·伊本·哈马德也屈服了，只剩下穆罕默德·伊本·努哈和我的父亲仍被关押。

“Then those present were put to the test. Those who withheld their assent were taken away and locked up. Of them all, only four resisted. Their names are Muḥammad ibn Nuḥ; ʿUbayd Allāh ibn ʿUmar al-Qawārīrī; al-Ḥasan ibn Ḥammād, called Sajjādah; and my father. Later ʿUbayd Allāh ibn ʿUmar and al-Ḥasan ibn Ḥammād gave in too, leaving only Muḥammad ibn Nūḥ and my father in confinement.