Muhammad Baqir Majlisi in his “Biharul anwar” 27/238 narrated:
التاركون ولاية علي عليه السلام المنكرون لفضله المظاهرون أعداءه خارجون عن الإسلام من مات منهم على ذلك
“Those who left wilayat of Ali (alayhi salam), rejected his superiority, and display emnity towards him, fall out of islam, if they died upon that”.
So what kind of conclusion could we have from this narration? If we would reject superiority of Ali over shaikhan, or reject ahadeth in his praise, that shias believe to be authentic, we are disbelievers in the view of shias