A national thanksgiving service will be held for the Queen's 90th birthday to celebrate her "humble devotion to Christ".

The Prime Minister will read from the New Testament during the service at St Paul's Cathedral on Friday and the Archbishop of Canterbury will preach a sermon in commemoration of the Queen's life.

Tributes to her Christian faith will be littered throughout the service, according to briefing notes released to journalists.

The first hymn will be 'O Worship the Lord in the beauty of holiness', which was chosen to recall "the Queen's Christian faith and her humble devotion to Christ". The Old Testament reading taken from Psalm 139 was chosen because it speaks "of God knowing us even before we are born and remaining with us at every stage of our lives".

This will be followed by a reading by David Cameron from Luke 12. This passage was chosen because it "encourages us not to worry about the things that God will supply for us but to focus on our faith in God's Kingdom – a focus which the Queen has observed throughout her life".

The service will be attended by a number of politicians and members of the royal family, and will reflect all aspects of the Queen's life, as well as her faith.

Representatives from all major Christian denominations in the UK will be present as well as representatives of other faiths. As part of the service they will offer "an act of thanksgiving for everything the Queen stands for", which will be led by the Bishop of London.

The prayers, led by six people, will feature descriptions of God taken from the book of Psalms.

The service will incidentally fall on the day of the Duke of Edinburgh's 95th birthday and a special reference will be made to that. 

The occasion will also be Sadiq Khan's first appearance at St Paul's Cathedral as the new Mayor of London. David Attenborough and the creator of Paddington Bear, Michael Bond, will offer "reflections on the passing of the years" near the end of the service. Both are celebrated figures in British culture as well as being fellow nonagenerians.

Attenborough and Bond's contributions mark a series of three items in the service intended as birthday gifts for the Queen. Another gift is an anthem specially written by Judith Weir which speaks of the "human desire to mirror divine creativity with our own humble efforts".

The Queen is Britain's longest reigning monarch after she surpassed the record of her great-great-grandmother Queen Victora on 9 September 2015. She was crowned on 2 June 1953.