These people, who make claims like the Messenger’s, are greater unbelievers than the Jews and Christians. What, then, of the Qarmatians, who fabricate lies against Allah more grievously than Musaylima did, deviate concerning Allah’s names and signs more grievously than Musaylima did, and wage war against Allah and His Messenger more fiercely than Musaylima did? A detailed account of their condition would be lengthy, but these pages cannot accommodate more than this.
What I have described is the condition of their imams and leaders who understand the true nature of their doctrine. Undoubtedly, some of the Shia and Rāfida who have joined them neither know the reality of their concealed beliefs nor inwardly agree with them. Such a person is a follower of apostate heretics, offering them allegiance and support. He is like the followers of those who teach union between Creator and creation: they offer them allegiance, revere them, and support them without understanding the true nature of their doctrine of the unity of existence—that the Creator is the creation.
Thus, whoever is inwardly a Muslim but, out of ignorance, reveres the teachings of Ibn ʿArabī, Ibn Sabʿīn, Ibn al-Fārid, and similar advocates of union is one of them. The same applies to anyone who reveres those who profess indwelling and union. These people’s relationship to the Jahmiyya is like those others’ relationship to the Rāfida and the Jahmiyya. Yet the Qarmatians are far greater unbelievers than the advocates of union. Thus, at best, their ordinary followers are Rāfidī Jahmīs.
Among the ordinary followers of the advocates of union, however, are people who are neither Rāfidīs nor outright Jahmīs. Rather, they do not understand their words and believe them to be the words of saints who have attained true spiritual insight. A fuller exposition of this answer belongs elsewhere. And Allah knows best.