Lang was born in a Roman Catholic family. Although he went to a Roman Catholic school, by the time Jeffrey was 16, he was an atheist. He converted to Islam in the early 1980s, and admits that he finds much spiritual satisfaction being a Muslim. Lang married a Saudi Muslim woman named Rakia and has three children, Jameelah, Sarah, and Fattin. In addition to numerous articles, he has written three books that are widely read among American Muslims. In his book Even Angels Ask: A Journey to Islam in America he shares with his readers the many insights that have unfolded for him through his self discovery and progress within the religion of Islam.
In recent times Mr. Lang has been an active voice in Islamic circles, and is one of the most recognizable inspirational speakers for Mecca Centric, an American Muslim educational organization. He serves as an Advisor and founding parent to the moderate North American group Generation Islam.