He is the Sheikh, most knowledgeable Muhaddith, Fadl al-Rahman Ibn Ahlullah al-Siddiqi, al-Ganj al-Muradabadi born in the year 1208.
He took the pattern chained (musalsal) narration of firstness (awwaliyyah) and Mahabbah and a portion of Sahih al-Bukhari from Sh. Abd al-Aziz al-Dehlawi. After his passing away he attended the study circle of his grandson Sh. Muhammad Ishaq al-Dehlawi, with whom he read the six books of hadith.
Sh. Fadl al-Rahman took the spiritual path from Sh. Muhammad Afaaq al-Naqshbandi al-Dehlawi whose company he kept and from whom he obtained his portion of knowledge and gnosis.
From the notable scholars that studied with him were:
-Sh. Badr Ali Shah
-Sh. Tajammal Hussein al-Bihari
-Sh. Abd al-Hayy al-Hasani and others
Al-Kattani said of him: He is the greatest of those who are narrated from in the lands of India, and the highest of them in terms of isnad.
Sh. Fadl al-Rahman narrated with a high isnad from the Muhaddith of India Sh. Abd al-Aziz al-Dehlawi, and the subsequent Muhaddith of India after his demise: Sh. Muhammad Ishaq al-Dehlawi. This great fortune of studying and narrating from both of them was a rare blessing and honour which few of his contemporaries were able to achieve.
He has a collection of his chains of transmission entitled ‘Ithaf al-Ikhwan bi Asanid Mawlana Fadl al-Rahman’ compiled by his student, the Musnid of the world (in his time): Abu Khayr Ahmad bin Uthman al-Attar al-Makki.
Sh. Fadl al-Rahman passed away with eight days remaining from Rabi al-Awwal in the year 1313, May Allah (the Exalted) have mercy on him and all those linked to him.
For further details refer to: Al-Ialam (8/384) of al-Hasani, Fihris al-Faharis (1/170)
Addendum: I do not usually paste from other websites, but wanted to point out this incident from the life of the Sheikh which indicates to his high standing and manners, as mentioned by Dr GF Haddad, who, when mentioning Sh. Siddiq Hasan Khan al-Qinnawji said: