There have been two interesting cases recently dealing with the separate but linked issues of the law relating to Volunteers in religious organisations and to ministers of religion.
In X v Mid Sussex Citizens Advice Bureau & Ors  EWCA Civ 28 the Court of Appeal rejected the suggestion that "Volunteers" were covered by the Anti-Discrimination provisions of the Equality Act 2010. (The case itself dealt with the provisions of EU Anti-Discrimination Directive but its findings would have affected the application of the 2010 Act)
The case involved a volunteer at a Citizens Advice Bureau and whether she was protected under the (now repealed) Disability Discrimination Act however it was common ground that the decision would involve all volunteers for any voluntary organisation and would apply to all types of Discrimination covered by the 2010 Act. What the Court of Appeal decided was that the Directive, and hence the Act, only applied to employees and not volunteers.
This decision is of particular significance to all religious organisations because of the large number of volunteers that are always involved with churches, synagogues, mosques, gurdwaras temples etc. If the Equality Act had applied to volunteers then these organisations would have been faced with a potential bureaucratic nightmare as they would have to ensure that every volunteer post was filled in accordance with equality guidelines with the possibility of facing Tribunal claims from disaffected parishioners who felt that they had been overlooked for appointment to a voluntary post. The fact that the law does not apply to volunteers lifts this potential threat from all voluntary organisations and allows them to get on with their primary role
In Moore v The President Of The Methodist Conference BAILII: UKEAT 0219_10_1503 the Employment Appeals Tribunal decided that a Methodist Minister was an Employee for the purposes of Employment Law, in this case a claim for unfair dismissal. The EAT applied an earlier House of Lords case Percy v. Church of Scotland  UKHL 73 in which the House of Lords decided that a Church of Scotland Minister was an employee
Prior to Percy the general assumption in law was that religious ministers, of all denominations, were office holders rather than employees and so were not protected under unfair dismissal and/or discrimination law. In Percy however the House of Lords decided that, on the specific facts, the Minister in the case was an employee and the same decision was made in Moore as regards a Methodist minister.
How far this principle will extend is difficult to determine. It is possible that Denominations which have a very sacramental view of the status and role of the Clergy, such as the Catholic and Orthodox Churches, will continue to be able to claim that their clergy are "office holders" rather than employees. However for Free Church Ministers, Rabbi's and Immans the position may be different and they may be held to be employees of their respective congregations should they decide to sue for unfair dismissal or discrimination.