Although the date of this document is uncertain, I think it may be taken in connection with a general meeting called by Julius III., the incidents of which are recorded by Vasari.
Michelangelo must have demonstrated his integrity, for he came out of the affair victorious, and obtained from the Pope a brief confirming him in his office of architect-in-chief, with even fuller powers than had been granted by Paul III.
VIII Vasari at this epoch becomes one of our most reliable authorities regarding the life of Michelangelo.

He corresponded and conversed with him continuously, and enjoyed the master's confidence.

We may therefore accept the following narrative as accurate: "It was some little while before the beginning of 1551, when Vasari, on his return from Florence to Rome, found that the sect of Sangallo were plotting against Michelangelo; they induced the Pope to hold a meeting in S.
Peter's, where all the overseers and workmen connected with the building should attend, and his Holiness should be persuaded by false insinuations that Michelangelo had spoiled the fabric.

He had already walled in the apse of the King where the three chapels are, and carried out the three upper windows.

But it was not known what he meant to do with the vault.