By 1863, Mirza Husayn Ali, a Babi from Nur, took the title Baha'u'llah, and claimed to have received divine revelation in fulfillment of Jewish, Christian, Islamic and Babi teachings. Baha'u'llah never advanced personal claim to civil authority, and required Baha'is to show obedience to government. As clergy and government officials became threatened by the advancing spread and acceptance of Baha'i teachings, Baha'u'llah was exiled to various locations throughout the Ottoman empire. Baha'u'llah died in 1891, still a prisoner in exile, and was buried in the place he was last imprisoned by the Ottoman empire, in what is now Akka, Israel. The public persecution of Baha'is has served a social function for the Iranian government.
Confession is one element.
Part of the aim is recantation and admission that the socio-religious order of the clerics is correct. As was observed earlier, the Iranian Constitution anticipates the return of the twelfth Imam so that the rule of the nation may be placed under his divine governance. Thus, the claims of the Baha'is form a religious and political threat from the government's perspective. While Baha'is believe Baha'u'llah's claim to be the twelfth Imam, there was no claim made to state governance at that time, or since. It is the Iranian government, by its own constitutional provision, that has conditioned its legitimacy up until the time of the return of the twelfth Imam.