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;
And them that worship the host of heaven - Saba: whence, in contrast to Sabeanism, Yahweh is called Lord of Sabaoth.
Upon the house-tops - which were flat (2 Kings 23:5-6; 2 Kings 23:12; Jeremiah 19:13, "All the houses upon whose roofs they have burned incense unto all the hosts of heaven, and have poured out drink offerings unto other gods." So also "unto Baal." The flat roofs, open to the sun and heavenly hosts, were chosen as the natural scene of worshipping those luminaries; so that, in fact, every house became an idolatrous sanctuary; (Jeremiah 32:29).
And them ... that swear by the Lord - rather, 'swear to Yahweh' (2 Chronicles 15:14, "And they sware UNTO the Lord with a loud voice"). The particle is a different one lª- from what follows, "them that swear BY [bª-] Malcham:" solemnly dedicating themselves to Him (cf. Isaiah 48:1, "Ye ... which swear BY [bª-, not the particle in Zephaniah] the name of the Lord ... but not in truth, nor in righteousness;" Hosea 4:15).
And - `and yet (with strange inconsistency) swear by Malcham' - i:e., 'their king' (1 Kings 18:21, "How long halt ye between two opinions? If the Lord be God, follow him: but if Baal, then follow him;" Ezekiel 20:39, "Go ye, serve ye every one his idols, and hereafter also, if ye will not hearken unto me; but pollute ye my holy name no more with your gifts, and with your idols;" Matthew 6:24, "No man can serve two masters; for either he will hate the one, and love the other; or else he will hold to the one, and despise the other. Ye cannot serve God and mammon"), (Maurer); the same as Moloch (note, Amos 5:26), and "Milcom the god of ... Ammon" (1 Kings 11:33). If Satan have half the heart, he will have all: if the Lord have but half offered to Him, He will have none.