The playhouse? The house of cards? The house of I?

One of the strange features of the Tarot de Marseille is that the 16th trump, called La Sagitta ("the Arrow") in the earliest Italian decks and The Tower in English, is known in the Marseille tradition as La Maison Dieu. It would be strange enough if it were called The House of God -- seeing as how it's being destroyed by fire from heaven and all -- but it's actually called The House God, without the preposition. 

Pierre Cheminade Tarot (1742)

I know of no other card in the Tarot de Marseille that omits de like this. It's always La Roue de Fortune, Valet de Baston, and so on. The house god is at least grammatical in English, where it means the god of the house, but this sort of "noun-banging" is not allowed in French. (Update: It turns out that maison-Dieu is good French after all; see the comments.)

So is the word de there after all? Consider the following:

• When de precedes a word beginning with a vowel, it is contracted to d' -- as in d'Alembert, langue d'oc, etc.
• Apostrophes are consistently omitted in the Tarot de Marseille, leading to such titles as Lestoille, Roy Despees, etc.
• J and U did not yet exist as separate letters when the TdM was created, but were written as I and V, respectively.

Taking all of this into account, is it possible that the name of this trump is actually La Maison d'Ieu -- or, as we would say in modern French, La Maison de Jeu? Jeu has numerous meanings, including "play" (as in a theatrical performance) and "deck" or "hand" (of cards).

I wonder, though, if de would really be contracted before a consonantal i. When Falstaff says "The Prince is a Iacke," he uses a rather than an because, though spelt with a vowel letter, Iacke was still pronounced Jack. I'm not familiar enough with archaic French to know whether they would have written de Iupiter or d'Iupiter, but I would bet on the former. Such forms as table d'hôte -- where de is contracted before a silent consonant letter -- suggest that French, like English, follows pronunciation rather than spelling. (Update: This is confirmed by the consistent use of LE IVGEMENT, rather than LIVGEMENT, in the Tarot.)

Could it be la maison d'ieu, then -- ieu being the Occitan form of the pronoun je? But maison does not appear to be an Occitan word.

I might as well also mention that the Pierre Madenié deck of 1709 labels this card La Maisonidieu -- whatever that means!