Charles Ellicott Commentary Isaiah 57:7

"Upon a high and lofty mountain hast thou set thy bed; thither also wentest thou up to offer sacrifice." — Isaiah 57:7 (ASV)

Set thy bed ... —Idolatry, being like adultery, the “bed” naturally follows as representing the locality of the idol worship. Compare to Ezekiel 16:31; Ezekiel 23:17.