Here are four options for people who want to come to the U.S. as a m-ssionary using the B-1 visa:

• Ministers of Religion coming on an Evangelical tour in the United States. This is for a person who will come to the U.S. and travel around preaching or speaking.   They can be supported by offerings contributed at each evangelical meeting.   But they can’t be using this “tour” to raise support for their work outside the U.S.  It is possible that this person needs to be ordained, but it is not clear.
• Ministers of religion temporarily exchanging pulpits with U.S. counterparts who will continue to be reimbursed by the foreign church and will draw no salary from the host church in the United States.
• General M-ssionary Service. This is for anyone, whether “ordained” or not, entering the United States temporarily for the sole purpose of performing m-ssionary work.   This has to be on behalf of a “denomination” .   It is not clear if the denomination has to have a presence here in the U.S. or it just means that a person has to be a member of a church, and sent by that church.  The person must receive no salary or remuneration from U.S. sources other than an allowance or other reimbursement for expenses incidental to the temporary stay. “M-ssionary work” for this purpose may include religious instruction, aid to the elderly or needy, proselytizing, etc. It does not include ordinary administrative work, nor should it be used as a substitute for ordinary labor for hire.
• In cases where an applicant is coming to perform voluntary services for a religious organization, and does not qualify for R status, the B-1 status remains an option, even if he or she intends to stay a year or more in the United States.
• Aliens participating in a voluntary service program benefiting U.S. local communities, who establish that they are members of, and have a commitment to, a particular recognized religious or nonprofit charitable organization. No salary or remuneration should be paid from a U.S. source, other than an allowance or other reimbursement for expenses incidental to the volunteers’ stay in the United States.