John Gills Exposition of the Bible Commentary - Isaiah 46:1
Bel boweth down, Nebo stoopeth ,.... These are names of the idols of Babylon. Bel is by some thought to be the contraction of Baal, the god of the Phoenicians, called by them Beel; so "Beelsamin" F8 Sanchoniatho apud Euseb. Praepar. Evangel. l. 1. c. 10. p. 34. , in the Phoenician language, is Lord of heaven: but rather this is the Belus of the Babylonians, who was a renowned king of them, and after his death deified; whom Nebuchadnezzar, according to Megasthenes F9 Apud Euseb.... read more
Matthew Henry's Complete Commentary - Isaiah 46:1-4
We are here told, I. That the false gods will certainly fail their worshippers when they have most need of them, Isa. 46:1, 2. Bel and Nebo were two celebrated idols of Babylon. Some make Bel to be a contraction of Baal; others rather think not, but that it was Belus, one of their first kings, who after his death was deified. As Bel was a deified prince, so (some think) Nebo was a deified prophet, for so Nebo signifies; so that Bel and Nebo were their Jupiter and their Mercury or Apollo.... read more