Imaam Al-Barbahaaree (rahimahullaah) said:

“And whenever you hear a man vilify the Aathaar or rejects the Aathaar or desire other than the Aathaar, then accuse him (of his Islaam) and do not have (any) doubt that he is a person of Hawaa (desires) and a mubtadee’ (innovator).”

Sharhus-Sunnah, p51