the exemption from the tax on self-employment income shall be effective for the first taxable year ending after 1967 for which such minister, member, or practitioner has net earnings from self-employment of $400 or more any part of which was derived from the performance of service in his capacity as a minister, member, or practitioner, and for all succeeding taxable years. See, however, paragraphs (b)(1)(ii) and (d)(2) of § 1.1402(c)-5 relating to ministers and members of religious orders and paragraph (b)(2) of § 1.1402(c)-6 relating to Christian Science practitioners.
26 C.F.R. §1.1402(e)-4A