Brotherhoods were non-monastic unions of Eastern Orthodox and Greek Catholic citizens or lay brothers affiliated with individual autocephalous churches. Some of their focus was of an evangelical or theological character, but much of their activities were in fact secular. Their structure resembled that of medieval confraternities and trade guilds, and can be characterized as the Orthodox equivalent of Catholic religious orders. Unlike the religious orders of other religions such as those of sufism in Islam, they do not hold any uniquely esoteric views or doctrines, or have initiative practices otherwise unfound in mainstream orthodox monasticism.