The definition is:
Quote Quoting Definition of Religious Workers
Religious workers include ministers of religion who are authorized by a recognized denomination to conduct religious worship and perform other duties usually performed by members of the clergy such as administering the sacraments, or their equivalent. The term does not apply to lay preachers. A religious vocation means a calling to religious life, evidenced by the demonstration of a lifelong commitment, such as taking vows. Examples include nuns, monks, and religious brothers and sisters. A religious occupation means a habitual engagement in an activity which relates to a traditional religious function. Examples include liturgical workers, religious instructors or cantors, catechists, workers in religious hospitals, missionaries, religious translators, or religious broadcasters. It does not include janitors, maintenance workers, clerks, fund raisers, solicitors of donations, or similar occupations. The activity of a lay-person who will be engaged in a religious occupation must relate to a traditional religious function: i.e., the activity must embody the tenets of the religion and have religious significance, relating primarily, if not exclusively, to matters of the spirit as they apply to the religion.
Also,
Quote Quoting Background Requirements
  • The applicant must be a member of a religious denomination having a bona fide nonprofit religious organization in the U.S.;

  • The religious denomination and its affiliate, if applicable, are exempt from taxation, or the religious denomination qualifies for tax- exempt status;

  • The applicant has been a member of the denomination for two years immediately preceding admission;

  • The applicant is entering the United States solely to carry on the vocation of a minister of that denomination, or, at the request of the organization, the applicant is entering the United States to work in a religious vocation or occupation for the denomination or for an organization affiliated with the denomination, whether in a professional capacity or not; and

  • The applicant has resided and been physically present outside the United States for the immediate prior year if he or she has previously spent five years in this classification.
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