A religious brother is a member of a Christian religious institute or religious order who commits himself to following Christ in consecrated life of the Church, usually by the vows of poverty, chastity and obedience. He is a layman, in the sense of not being ordained as a deacon or priest, and usually lives in a religious community and works in a ministry appropriate to his capabilities. A brother might practice any secular occupation. The term "brother" is used as he is expected to be as a brother to others. Brothers are members of a variety of religious communities, which may be contemplative, monastic, or apostolic in character. Some religious institutes are composed only of brothers; others are so-called "mixed" communities that are made up of brothers and clerics (priests or ministers, and seminarians).
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It is also common in many Christian groups to refer to other members as "brother" or "sister". In particular, the Christian Shakers use the title for all male adult members.