After learning the basic kitaabs by his uncle and Moulana Fateh Muhammed he proceeded to Deoband to complete his studies and qualified at the tender age of 19 or 20 years. From his student days he became famous for his intelligence and sharp wittedness. He never wasted his time in futile play and amusement. He had such a burning desire to obtain knowledge that he learnt certain kitaabs which he could not study during class times, from his ustaads while they were performing wudhu.
Moulana's ustaads were all great luminaries of their time. The most important amongst them was Moulana Muhammed Yaqub Saheb from whom he achieved the greatest amount of knowledge and spiritual benefit.
He learnt qiraat from the well-known Qari Muhammed Abdullah Saheb Muhajir Makki and mastered it to such an extent that it became difficult for the listener to distinguish between the recitation of the student and the teacher.
After qualifying he spent 14 years in Kanpur teaching, writing and propagating to the people. During this period thousands of students quenched their thirst at this "ocean of knowledge". Although Moulana was still very young, the people of Kanpur respected and honoured him tremendously and it was at that time that he became famous. His discourses were greatly appreciated and were being printed in the form of booklets. Very few scholars in the history of Islam have had so many of their discourses printed.
During his student days in Deoband he desired to make a pledge on the hands of Moulana Rasheed Ahmed Gangohi who refused, saying that it would harm his studies. Moulana then wrote a letter to Hajee Imdadullah in Makkah urging him to make Moulana Gangohi accept the pledge. Hajee Imdadullah instead by means of a letter accepted Moulana Thanwi as his disciple. When Moulana Thanwi accompanied his father for haj one year after qualifying he renewed his pledge at the hands of Hajee Imdadullah. After his return from Hijaz, he continued teaching and propagating while his desire for zikr intensified. He used to deliver lectures while standing 5,6 and sometimes even 7 hours continuously.
In 1315 A.H. he left Kanpur and on the advice of his spiritual mentor Hajee Imadadullah returned to Thana Bowan. This was all part of the divine plan of the Creator so that the Khanqah of Hajee Imdadullah would once again be reinhabited. This was the termination of the first phase of his life which was devoted more to deeni education. The second phase which began with his return to Thana Bowan was devoted more to imparting sprititual benefits to the masses. Moulana has written books in every field whether it be tafseer or tasawwuf, fiqh or tajweed. All his works total more than a thousand. In the field of hadis he did not write any voluminous work directly because he had many assistants. In this way the voluminous "Ila us Sunan" was written under his guidance. Regarding this kitaab he said that if this madressah does no other work besides the writing of this book, it will be a great achievement because it is a unique work. Perhaps very few Muslim homes do not posses "Behisti Zewar" and "Munajaat e Maqbool", two of Moulana's famous books. His tafseer "Bayanul Quraan" is unparalleled." Moulana Anwar Shah Kashmiri well known for his in-depth knowledge used to say that after reading Bayanul Quraan I developed a desire to read Urdu books. Although Moulana wrote such a large number of books, yet he did not earn a cent from them. All his work was solely for the pleasure of Allah. He has granted full permission to anyone who desires to print his books. Some of his works have been through hundreds of editions. Moulana used to say that Alhamdulillah all the necessary work has been done. The path towards deen has been cleared for centuries. Insha-Allah, my books, discourses and advices will be of assistance in deeni matters for future generations. This is all due to the blessings of Hajee Imdadullah.
On 20 Jamadul Awwal 1346 A.H. whilst performing Fajr Salaat he was inspired about the effects of certain acts. If the Muslims practised these acts, their calamities could be overcome. Consequently Moulana gathered 25 principles and had them printed in a booklet namely "Hayatul Muslimeen" (now available in English). Although Moulana has written over 1000 books, yet he had this to say: "I never had any thought of any of my books being a means of salvation for me. However, with regards to Hayatul Muslimeen, I have a strong feeling it will be a means of my salvation. I regard it as the earning and capital of my entire life."
Moulana Thanwi spent his entire life serving deen in every field. It is for this reason that he has been given the titles Hakimul Ummat and Mujaddid-e-Millat. After blessing the earth for 83 years with his presence, he passed away on 16 Rajab 1362 A.H. (20 July 1943). Namaze Janazah was performed by Moulana Zafar Ahmad Usmani. Moulana Thanwi was buried in the graveyard - Ishq-Bazaan of Thana Bowan.