And them that worship the host of heaven upon the housetops; and them that worship and that swear by the Lord, and that swear by Malcham; (Zephaniah 1:5)
From ancient times the sun, moon, and stars have been worshiped as representatives of the powers of nature and prime movers of earthly events (see Jer. 8:2; 19:13; see on Deut. 4:19). Manasseh, king of Judah, and probably a great-great-uncle of Zephaniah (see on Zeph. 1:1), especially fostered this worship (see 2 Kings 21:3).
Housetops.
On these flat roofs families made altars to worship the heavenly bodies, offered animal sacrifices, and burned incense (see on Jer. 19:13).
That swear.
The last half of v. 5 refers to the compromisers who combined the worship of the Lord with that of stars and other gods.
Malcham.
The Ammonite god, more correctly called Milcom, mentioned in several ancient documents. See on 1 Kings 11:7.