He was one of the most distinguished graduates of Darul Uloom. After his graduation from it in A H 1321, Hadhrat Shaikhul Hind selected him for Madrasah Naumania Pureni, District Bhagalpur (Bihar). Accordingly, he taught there for nearly seven years. Then he came to Shahjahanpur and established a Madrasah under the name ‘Afzalul Madaris’ in a mosque where he taught for the sake of Allah (i.e. without charging any fees or taking any remuneration). For nearly three years he taught very successfully in this Madrasah. In A H. 1330 he was appointed as a teacher in Darul Uloom Deoband, and in the first year he was assigned elementary books of Arabic like ‘Ilmus Sigha, Nurul ¬Ezah, etc. In the report for that period it has been stated about this Professor of Literature as under: ¬ “He (Maulawi Izaz Ali) has been a teacher at some places. He is a young, talented, righteous and pious scholar. In complexion and character he is a relic of his ancestors. He has complete proficiency in different sciences and great expertise particularly in the science of literature. He teaches in the middle classes of Darul Uloom. He handles most of the lessons of the science of literature. He also exercises the students in writing Arabic articles. He is an eloquent lecturer; the students are very familiar with him”.
In A H 1340, when Maulana Hafiz Muhammad Ahmed, vice-chancellor of Darul Uloom Deoband, was selected for the post of the Chief Mufti of the erstwhile Hyderabad State, so he on account of his old age, took Maulana Izaz Ali with him. There he stayed one year and came back with Hafiz Sahib to Deoband. In the vacancy of the Chief Mufti Maulana Azizur Rahman, he was appointed as Chief Mufti of Darul Uloom Deoband, on which post he stayed in Darul Uloom till his demise. Religious jurisprudence (Fiqh) and literature were his special fields. Initially when he came to Darul Uloom Deoband, he had been assigned elementary books of Arabic, but at last his teaching attained such popularity that he became famous by the title of “Shaikhul Adab wal-Fiqh” (Professor of Literature & Jurisprudence). In the last phase of his life he also taught for several years the second volume of the Tirmizi and also higher books of Tafsir. In Maulana Hussain Ahmad Madani’s absence, he also had several times the chance of teaching the Bukhari Sharif also. Along with teaching he had also had a special penchant for training and looking after the students; a quality from which the students benefited very. His punctuality was proverbial and in his punctual engagement of his classes he was sui generis.
From the very inception of teaching till his last breath he was meticulously punctual in his work. He was a paragon of selflessness and humility. He would never feel ashamed of teaching the most elementary books along with the highest books; teaching at-Tirmidhi and al-Bukhaari (to higher classes), he would gladly teach Mizanus Sarf, Ilmus Sigha, Nurul Ezah, etc. to small children also. The most beloved student in his eyes would be one who devoted himself to studies with singleness of purpose and the most hated would be one who engaging in pastimes, showed carelessness in studies, though such a student be his own son.
Even as this professor of literature had great mastery in writing Arabic prose and poetry, he was equally highly proficient in composing Urdu prose and poetry also. He had a special style in Urdu prose. Though his hand was not quite legible, the style of writing was such that it looked pleasing to the eye. In Arabic literature, he had compiled a book entitled Nafahatul Arab comprising historical anecdotes, fables and moral themes. This book became very popular in Arabic schools and as such was included in the syllabi of Darul Uloom and many other Madrasas. Besides this, he has written many useful notes on many books of Fiqh and Arabic Literature, which are highly appreciated in the circle of scholars.
His ability in administrative matters too was acknowledged on all hands and his administrative know-how was often utilized in the management office also. In short, he was an incomparable teacher, an erudite religious divine and a versatile personality. The period of his academic services in Darul Uloom extended over 44 years.
He was entrusted with the post of Ifta twice: first time from 1347 to 1348, and second time from 1364 to 1366. During his period, 24,855 fatwas were written. He passed away in 1374 (1955).