Anyone employed as a Minister of Religion, whose remuneration in respect of that employment doesn't consist wholly or mainly of stipend or salary are regarded as self-employed earners for National Insurance Contributions (NICs) purposes. HM Revenue & Customs (HMRC) will send you a bill once a year to pay Class 2 NICs voluntarily if you wish.
HMRC will register you for Self Assessment. When you fill in your return you must fill in the additional sections known as supplementary pages.
Follow the link below (on the GOV.UK) for more information about the supplementary pages. https://www.gov.uk/self-assessment-forms-and-helpsheets