Imaam Ibn Katheer (rahimahullaah) said:

”They are a forsaken group and a despicable sect that follow ambiguities and abandon the entirely clear affairs that have been determined by the Imaams of Islaam amongst the Sahaabah, the Taa-bi’een and those who came after them amongst the scholars who are (highly) recognized in all eras and regions of the earth.” [Al-Bidaayah Wan-Nihaayah: 5/287]