The doctrine expresses the Ismaili conviction that revelation requires continuous, authoritative interpretation adapted to changing circumstances, and it underlies the community's notable institutions of education, health, and development directed by the Imamate. It distinguishes Nizari Ismailism sharply from Sunni Islam, which recognises no such ongoing office, and from Twelver Shiism, whose Imam is awaited rather than present. The belief is inseparable from the Ismaili understanding of the batin, since the Imam is held to be the one who unlocks the inner meaning of scripture. The contrast with Twelver Shiism is precise: the twelfth Imam, Muhammad al-Mahdi, is held by Twelvers to have entered occultation beginning in 874 CE and to remain hidden until his return, so that the community has had no manifest, present Imam for over eleven centuries and relies instead on the collective juristic authority of its clergy (marja) in his absence.
Nizari Ismailis point to their own unbroken, visible line as the substantive difference the doctrine of the living Imam makes: instead of a jurisprudence developed by scholars interpreting texts in the Imam's absence, the community looks to direct guidance, embodied in recent decades in institutions such as the Aga Khan University, founded in Karachi in 1983, and the wider Aga Khan Development Network.