Marchosias's entry ends with one of the strangest lines in the catalogue. Having answered truly and fought strongly for whoever calls him, he tells the operator that after twelve hundred years he hopes to return to the seventh throne, and the text adds, in most readings, that this hope is vain.
The passage is doing several things at once.
It assumes a fall, and a hierarchy from which the spirit fell, and a numbered rank within it. None of that is stated anywhere else in the book. The seventh throne implies a scheme of thrones, and the nearest available one is the nine celestial orders of Pseudo-Dionysius, in whose Celestial Hierarchy the Thrones are a named choir. Whether the compiler meant that, or meant something numbered differently, is not recoverable.
It assumes a term. Twelve hundred years is a specific sentence, and the idea that a fallen spirit might serve out a period and be restored is a version of the apokatastasis, the eventual restoration of all things, including the damned, which was argued in the early church, associated with Origen, and condemned. It is a live theological position appearing, unattributed, in a seventeenth-century compilation about demons.
And then the text takes it back. The hope is called vain, which is the orthodox correction to the heterodox idea the sentence has just voiced. A reader can see the compiler's hand: a piece of inherited material is reproduced, and a clause is added to make it safe.
Belial's entry carries a related note, that he was created next after Lucifer. Between them these two lines are almost the entire cosmology of the Goetia, and both are asides.