On the 4th of November 1952 Queen Elizabeth made, before the UK Parliament, the Accession Declaration as required by the Accession Declaration Act of 1910.
The wording is as follows;
"I, Elizabeth, do solemnly and sincerely in the presence of God profess, testify, and declare that I am a faithful Protestant, and that I will, according to the true intent of the enactments which secure the Protestant succession to the Throne, uphold and maintain the said enactments to the best of my powers according to law."
(Hansard 4 November 1952)
The 1910 amendments to the legislation, brought in at the behest of citizens in UK, Canada and Australia who objected to the robust anti-Catholicism of the previously prevailing legislation, still preserve the 'true intent' of those previous enactments which repudiates the Roman Catholic doctrine of transubstantiation - the belief that the body and blood of Jesus Christ materialises in the communion service - and rejects the authority of the pope and the adoration of the Virgin Mary.
Unless the Accession Declaration Act 1910 is amended or abolished the next monarch will have to make the same declaration before the UK Parliament or at his or her coronation.
For more information
R.M.Morris Church and State in 21st Century Britain. Basingstoke: Macmillan
Norman Bonney 'Modernising the Monarchy: The Oaths of Office'. The Political Quarterly 2010, 81, 4, 564 - 570
A copy of the declaration on the UK Parliament website can be seen at the following url;
If this url does not link to the item search for 'Accession Declaration' in the website www.parliament.uk