Sh. Wahbi Suleiman Ghawji also mentions this ‘turnaround’ in his introduction to Sh. al-Luknawis critique of Nawab Siddiq Hasan Khan wherein he says (pg.5-6):
Sh. Nur al-Hasan Khan the son of Sh. Siddiq (Hasan Khan) said regarding his father: When I saw prayer beads in his hand for the first time I was amazed and asked him about it. He replied to me that he was constantly making istighfar since Sh. Fadl al-Rahman al-Muradabadi had advised him to do so…He then said: He was overcome by enlightened states until he was fortunate to repent from his previous bad opinion of the Imams of fiqh and tasawwuf. He wrote this at the end of his ‘Maqalat al-Ihsan wa Maqamat al-Irfan’ which is a translation of ‘Futuh al-Ghaib’ of Sh. al-Imam Abd al-Qadir al-Jili (Jilani).
This incident is worth reflecting over for various reasons. Not least that it is evidence of Sh. Fadl al-Rahman al-Muradabadi’s lofty character. Here he has one of the most notable of the scholars of the anti tasawwuf movement contacting him asking to take bayah with him. His response was to send Nawab Siddiq his turban and advised him to make istighfar, dealing with him in a manner to honour him and show him respect, as opposed to humiliating him or parading him as a trophy in an attempt to show how great a Sheikh of tasawwuf he was.
It also shows Nawab Siddiq Hasan Khans sincerity and desire to make amends for his previous views, and courage in contacting a major sufi Sheikh and humbling himself before him to ask him to accept him as a murid of his.
This incident also reminds me of something I heard a while back about Sh. al-Sabuni, the Syrian expert in Tafsir taking bayah with Sh. Mahmud Effendi in Istanbul. Both of these scholars are of a similar age.