Lay sister

In the past, the term lay brother was used within some Catholic religious institutes, to distinguish members who were not ordained from those members who were clerics (priests and seminarians). This term is now considered controversial by some because of the history of inequality between Brothers and clerics. The term "lay" has also been used in the past to designate someone as "uneducated" in contrast to "illiterate." Instead, the term "religious Brother" or simply "Brother" is appropriate when referring to a vowed male religious who is neither priest, deacon, nor seminarian. The vocational title "Brother" is generally capitalized in order to distinguish it from the generic use of the biologically relational term "brother."

In religious communities today, religious Brothers are no longer restricted by the institutional inequalities of the past and enjoy the same status, rights, and opportunities as their priest and seminarian confreres, except where sacramental ministry is concerned. Brothers today (at least in the United States) generally pursue academic, professional, or technical training that is appropriate to their interests and skills and can be found in a variety of ministries. Many Brothers also study theology, scripture, and philosophy to some degree, although there is a great deal of variance regarding the intensity and duration of these academic curriculums.

Although religious life began with communities of desert hermits and monks in which none of the members were ordained, over time the Church began to blend monastic life with the ordained ministry. Within this context, a rigid hierarchy eventually emerged in which the lay Brothers were restricted to ancillary roles, manual labor, and other secular affairs of a monastery or friary. In contrast, the choir monks (priests and seminarians) of the same monastery attended to the Liturgy of the Hours, or Opus Dei ("The Work of God"), sacramental ministry, celebration of the liturgy, and formal studies. The term is also used of those who are Brothers in those religious congregations which have been established since the Reformation. While taking vows particular to their religious community they have not been ordained by a bishop as deacon or priest. In this regard they are considered "lay religious," where "lay" simply means "non-clerical."

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