Imam Rabbani Shaikh Ahmed Sirhindi (Allah have mercy on him) wrote,

‘No practice of any Sufi is an argument to decide that which is lawful or unlawful.

(If something is questionable reported about them) Instead of reproaching them we pass over their actions and leave them to the judgement of Allah.

This (determining of what is halal or haram) is a matter in which the opinion of Imam Abu Hanifa, Imam Abu Yousuf or Imam Muhammed should be considered authoritative rather than the practice of Abu Bakr Shibli or Abul Hasan Nuri (Allah have mercy on them all).’

Maktubaat Imam Rabbani ra, volume 1, letter 266