Upon a lofty and high mountain hast thou set thy bed,.... Temples and altars, which are usually built on high places, where they commit spiritual adultery; that is, idolatry, in imitation of the Heathens, who had their temples and altars on high places; and the idolatry of the church of Rome, in this context, is all along expressed in language agreeable to the Heathen idolatry, and in allusion to it.
Some think this phrase denotes impudence in their idolatrous worship; for not content to worship under trees, in valleys, and under clifts of rocks, and such dark places; now, as not blushing at, or being ashamed of their actions, erect their altars in the most public places.
Perhaps some reference may be had to the city of Rome itself, built on seven mountains, the seat of antichrist, and where the principal bed for idolatry is set up. The Targum is,"on a high and lofty mountain thou hast the place of the house of thy dwelling;''which agrees very well with the great city, the seat of the beast.