Nicæa I: canon XI

Concerning those who have transgressed without necessity or the confiscation of their property or without danger or anything of this nature, as happened under the tyranny of Licinius, this holy synod decrees that, though they do not deserve leniency, nevertheless they should be treated mercifully. Those therefore among the faithful who genuinely repent shall spend three years among the hearers, for seven years they shall be prostrators, and for two years they shall take part with the people in the prayers, though not in the offering.