Yazdani joined the group in his early youth, introduced Jamaat to people in Delhi, organized its activities in Delhi which later emerged as a zone. He led the Jamaat Delhi and Haryana Zone as its regional chief for over a decade. Then he joined the group's headquarters as Dawah secretary.

He also edited Kanti Hindi weekly for about 35 years. Yazdani translated most of the basic literature into Hindi before the establishment of Hindi section. Most prominent of his translated works include Hindi translation of Talkhees Tafheemul Quran and a hadith selection titled Hadith Saurabh.