I would like know if he has to belong to the Church of England.
Like the Queen?
All members of parliament have to take an oath of allegiance to the Queen, which could be viewed as an oath to the CofE. Technically, a Catholic is forbidden from holding the post of PM…however, Tony Blair has strong Catholic leanings, and his wife is a practising catholic. So I guess in that trtuly British manner, you can get away with anything as long as you keep quiet about it 
No, The current leader of the Her Majesty’s oppositon (currently the Conservatives), Micheal Howard is nominally Jewish and the previous holder of this post Iain Duncan Smith was a Catholic as indeed is the leader of the third party (the Liberal Democrats) - Charles Kennedy (should their respective parties win the next general election they would become Prime Minister).
I’m not sure of the religonm of previous holders of this office, but Tony Blair is a member of the CoE.
Nope. In fact, Benjamin Disraeli was a Jew, and I think there are a few Catholics in there.
Benjamin Disareli, despite his families Jewish roots, was though a practicing member of the Church of England as his father converted to the CoE. IIRC at the time he first became an MP it was still a post forbidden to non-Protestants (soon after Catholics were allowed to become MPS and a decade or two later Jews were allowed to become MPs).
Benjamin Disraeli (PM in 1868 and from 1874 to 1880) was Jewish but to become Prime Minister he “became” Anglican, but that was some time ago.
Today, I don’t think it would really matter.
(The oath of allegiance is a formality. I have seen footage of known republican MP’s laughing when making their oath to the queen and reading it in a mocking way).
I’d have to look it up to be 100% certain, but I am pretty sure that Benjamin Disraeli was baptized into the CoE as an infant due to his father’s conversion.
Bonar Law was a Presbyterian, as I believe was Ramsay MacDonald. There has never been a Catholic PM, but there’s nothing constitutionally to prevent one.
Disraeli was baptized in the CoE but always thought of himself as a Jew, and since he had Jewish lineage on his mother’s side he was certainly a Jew by Jewish standards.
When an anti-semitic MP objected, he is quoted as saying,
At which point the other MPs all went “Oh, snap!”
And according to the official record Disraeli became an Anglican at the age of 12.
Yes, he certainly did not deny his Jewish heritage, but his relgion was certianly CoE.
To answer the OP: no. The monarch has to be C of E, but not the PM.
Of course, how one is supposed to tell whether one is C of E or not is rather an abstruse metaphysical point.
I’m pretty sure that Margaret Thatcher is a Methodist.
Curiously, Harry Turtledove has Confederate SecState Judah Benjamin (a Jew) deliver a variation on this line in Guns of the South.
there are no rules concerning the religion of the P.M.
The Act of Settlement 1701 bars Catholics from the Throne or from the line of succession and requires that the Sovereign be In Communion with the Church of England. Implicitly it bars Jews, Muslims and Dissenters as well, although it doesn’t actually say so, probably because the idea that a Muslim would ever be in line for the Throne would have struck the government of the day as ludicrous.
Church of England clergy were barred from standing for election to the House of Commons because they were already represented in Parliament by the Bishops in the House of Lords. Likewise Peers Of The Realm could not stand either. (Note that some people with a title who were not qualified to sit in the Lords, such as eldest sons of Peers who had a courtesy title, could and did get elected to the Commons. Churchill’s father, Lord Randolph Churchill, being an obvious example)
Both these rules have recently been changed.
Margaret Thatcher’s father was a Methodist lay preacher, which would lead me to believe that she was also Methodist.
Well the queen appoints the bishops of the Church of Enland on the advise of the Prime Minister?
That’s technically true, but it doesn’t depend on the Prime Minister having any personal religious views. A shortlist of candidates is presented to the PM with arguments for and against each one put forward by interested parties; the PM chooses one on the basis of those recommendations.
IIRC according to Peter Hennessy’s book on the position of the Prime Minister, the PM’s appointments secretary must be a practicising Anglican in order to give the PM the list Everton mentioned.
The Catholic Emancipation Act 1829 included a list of positions which could not be filled by a Catholic - these included Regent, Lord Chancellor and Lord Lieutenant of Ireland. There was no prohibition of a Catholic filling the role of Prime Minister.
Last year, the General Synod of the Church of England debated rejecting the PM’s role in appointing bishops. Those in favour of a change argued that they objected to a holder on an essentially secular post having any influence over church appointments; there wasn’t any stress on that person being religious but not Anglican.
They decided to keep the current situation because they calculated that it would lead to the disestablishment of the CofE. The reason that the PM is involved in the selection procedure is not because he or she has to be an Anglican but because of the automatic appointment of bishops to the House of Lords (which no longer applies anyway).