I recently posted Black Rod and the Door of the House of Commons based upon a piece on the History of Parliament website about the origins of this ceremonial at the State Opening of Parliament and the apparent modern misinterpretations of its significance.
Since then the online Liturgical Arts Journal has published a piece about medieval French processional practice on Palm Sunday, which I think reinforces my own argument for drawing the parallel between the state and religious ceremonies. The full article, which is very interesting in itself, can be seen at Singing on High: The Gloria Laus Ceremony of Palm Sunday in Medieval France
In it there are a sequence of passages from the early eighteenth century liturgical French commentator Claude de Vert, Explication Simple, Littérale et Historique des Cérémonies de l'église, Volume 2, pp. 377 - 384, about the liturgy of Palm Sunday, notably that of knocking with the Processional Cross on the city gate or church door for admission. That is done in the name and with the symbol of the King of Kings, but very much on the same principle as was considered in respect of the English monarch and the House of Commons, and its possible inspiration with the City of London, by the original History of Parliament post.
Claude de Very in his turn compares the Palm Sunday practice with the ceremonial of Joyeuse Entrees by the Kings of France with the significant interpretation:
“the church doors are closed so that they may be opened again, and in this manner the procession is honoured, as if the doors were only opened for the express purpose of welcoming it.” (from Section 19).
This seems to me to tie in closely with the History of Parliament blog post about the origins of the closing of the doors of the Commons at Black Rod’s approach and their immediate opening upon his or her striking the door in the name of the Sovereign.