Took every man his garment, and put it under him - The outer cloak of the Jews was a sort of large shawl or blanket, which might well serve for a carpet of state. Such a carpet is commonly represented on the seat of an Assyrian throne in the Nineveh sculptures.
The stairs rose against the walI of the house from the pavement of the court to the level of the upper story, or of the roof. At the top of the stairs would be a flat platform, and this would form a throne, on which the new king could exhibit himself to his subjects.
Blew with trumpets - On this recognized part of the ceremony of a coronation, see 2 Kings 11:14; 2 Samuel 15:10; 1 Kings 1:39.