The anointing oil that will be used in the coronation service of King Charles has been consecrated today in Jerusalem at the Church of the Holy Sepulchre.

In what the Archbishop of Canterbury called a nod to the King's "personal" connection to the country, the Blessed Patriarch for Jerusalem — from the Greek Orthodox Church — shared in the consecration with an Anglican Archbishop, the church of which Charles is now head.

This is a break with tradition from his mother, whose anointing oil was consecrated by the Bishop of Gloucester.

The consecration of the oil involved mixing olive oil from the Mount of Olives with essential oils for scent, which is then blessed, so it becomes 'Chrism' oil.

The coronation of King Charles will see him officially crowned as monarch, and formally mark a new chapter with him as head of the Royal Family.

The ceremony — which will take place at Westminster Abbey on Saturday 6 May — is primarily a religious one, and will be administered by the Archbishop of Canterbury.

When he became King, Charles also became the Supreme Governor of the Church of England, which means these religious aspects will be significant — especially for attendees of the Anglican Church, even if those numbers are trending downwards.

One important aspect of the coronation ceremony is when the monarch is anointed with oil — this was seen as religiously so important and transformative that it was the one moment that wasn't televised during Queen Elizabeth's 1953 coronation.

What is anointing oil?

The oil that will used to anoint Charles as sovereign has been made from sesame, rose, jasmine, neroli, benzoin cinnamon, orange blossom and amber oils for scent, and olives from groves in two monasteries on the Mount of Olives, Jerusalem.

The exact recipe isn't known, but in a personal touch one of the monastery groves which was selected is also the burial place of King Charles's paternal grandmother — Princess Alice of Greece.

The oil will also be used to anoint Camilla as she crowned as Queen Consort, and is based on the recipe used for Queen Elizabeth's coronation.

Normally, a batch of the oil is made to last for several coronations, but during the Second World War a bomb hit the deanery where it was being stored, so the late Queen's coronation was the first to use the new batch and Charles has also opted for a fresh batch to be made.

Why does the King get anointed?

The oil is seen as holy, and used to consecrate and sanctify them as sovereign and for the duties that are required of the role.

The basis of this practice goes back to the Old Testament, initially this was used for priests, prophets and objects that would be placed in the tabernacle — the tent that the Israelites would congregate in.

Later, this was extended to kings, and during the anointing part of the coronation Zadok the Priest has been sung at every ceremony since 973 AD.

The words to this anthem come from the part of the Bible when a priest, Zadok, anointed Solomon and announced him David's successor as king.

Since 1727, these words have been sung to music composed by Handel.

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