It is reported that Al-Fudayl b. ‘Ayyâd – Allâh have mercy on him – said, “Whoever helps an adherent of bid’ah (heretic) has helped in the destruction of Islam.”
Abû Nu’aym, Hilyatu Al-Awliyâ` Vol. 1 p398.
It is reported that Abû Ishâq Al-Hamdânî and Ibrâhîm b. Maysarah said, “Whoever respects an adherent of bid’ah has helped in the destruction of Islam.”
Reported from Al-Hamdânî by Al-Âjurrî, Al-Sharî’ah Vol. 5 p260; and from Ibn Maysarah by Al-Lâlakâ`î, Sharh Usûl I’tiqâd Ahl Al-Sunnah Vol. 1 p265.