Does a member of a mission organization, who has been commissioned, qualify for the ministerial housing allowance even though not performing sacerdotal duties?
It depends, but here's the general guideline from Treas. Reg. § 1.107-1(a): "examples of specific services considered duties of a minister."
-- Performance of sacerdotal functions;
-- Conduct of religious worship;
-- Administration and maintenance of religious organizations and their integral agencies;
-- Performance of teaching and administrative duties at theological seminaries.
Publication 517 further helps to define ministers in parachurch organizations. I'll provide the entire section to give readers some context.
"Most services you perform as a minister, priest, rabbi, etc., are qualified services. These services include:
-- Performing sacerdotal functions,
-- Conducting religious worship, and
-- Controlling, conducting, and maintaining religious organizations (including the religious boards, societies, and other integral agencies of such organizations) that are under the authority of a religious body that is a church or denomination.
"You are considered to control, conduct, and maintain a religious organization if you direct, manage, or promote the organization's activities.
"A religious organization is under the authority of a religious body that is a church or denomination if it is organized for and dedicated to carrying out the principles of a faith according to the requirements governing the creation of institutions of the faith.
"Services for nonreligious organizations. Your services for a nonreligious organization are qualified services if the services are assigned or designated by your church. Assigned or designated services qualify even if they do not involve performing sacerdotal functions or conducting religious worship.
"If your services are not assigned or designated by your church, they are qualified services only if they involve performing sacerdotal functions or conducting religious worship."