Hakim al Umma Maulana Ashraf Ali Thanvi (Allah have mercy on him) instructed,

‘Neither have conviction about, nor associate with a person who appears to be a Sufi but contravenes Sharia (laws). This is irrespective of his having unveiling (kashaf) or miraculous incidents (karamat).

However, do not criticize anyone without a genuine reason.’

Ta’leem ut Talib, #9, p23