The Act of Union 1707 made this function redundant, but a Lord High Commissioner to the General Assembly of the Church of Scotland has been appointed each year, as the monarch's personal representative, since 1690.

The Lord High Commissioner sits on the throne in the Royal Gallery, which is technically "outside" the Assembly Hall—symbolising the independence of the Church in matters spiritual from state interference.

[2] The first General Assembly of the newly united church in 1929 was held in halls in Annandale Street, Edinburgh (now a bus garage), the only building large enough.

Difficulty in accessing the Royal Gallery in this temporary location led to a seemingly trivial but nevertheless embarrassing dispute over protocol, whereby the Lord High Commissioner (the Earl of Inverness, later King George VI) would have had to enter through the Assembly Hall itself—an act of symbolic state interference in the hard-won spiritual independence of the church.

Apart from his/her opening and closing addresses, the Lord High Commissioner makes no further intervention in Assembly debates but will be in daily attendance for at least part of each day's business.

However, the plates are re-attached during the closing speech of the Assembly, and the Lord High Commissioner returns to his royal but temporary residence as an ordinary citizen.

The Household make no financial demands on the funds of the Church of Scotland, which are devoted exclusively to the Parish and Mission work of the Kirk.