He says:

Ḥusayn ibn ʿAbd Allāh related: “I asked Abū Bakr al-Marwazī ⦗1⦘ about the affair of Ibn al-Thallāj. He told me:

‘Abū ʿAbd Allāh, Hārūn al-Ḥammāl ⦗2⦘ came to me and said, “Ibn al-Thallāj has repented of keeping company with Bishr al-Marīsī; shall I bring him to you?” I replied, “No⦗3⦘—I do not want anyone to see him at my door.” He answered, “I would like to bring him between the sunset and night prayers,” and he continued to press me. I said, “Here he is saying, ‘Come!’⦗4⦘—what am I to tell you?” So he brought him.

I said to him, “Go until your repentance is sound and proclaim it openly⦗5⦘.” He departed, and later we were informed that he had declared waqf—suspending judgment.

Abū Bakr al-Marwazī ⦗6⦘ continued: I went to him with two of our companions and said, “Something has reached me about you⦗7⦘, though I have not accepted it.” He asked, “What is it?” I said, “You are suspending judgment concerning the Quran⦗8⦘.” He replied, “I say: it is the Speech of Allah,” and he began to cite Yaḥyā ibn Ādam and others, claiming that they too had taken this stance.

I said to him, “This comes from the book that ʿUbayd ibn Naʿīm bequeathed to you.” He responded, “Do not mention people.” I said, “Do all the Muslims not unanimously agree that if someone swears by a created thing, no expiation (kaffārah) is due?” He said, “Yes.” I said, “Then when someone swears by the Quran, have they not unanimously required an expiation because he has sworn by something uncreated?” He replied, “That is the merchandise of the dialecticians.’”