Jamieson, Fausset & Brown

They . . . that erred-- (Isa 28:7). learn doctrine--rather, "shall receive discipline" or "instruction." "Murmuring" was the characteristic of Israel's rebellion against God (Exo 16:8; Psa 106:25). This shall be so no more. Chastisements, and, in HORSLEY'S view, the piety of the Gentiles provoking the Jews to holy jealousy (Rom 11:11, Rom 11:14), shall then produce the desired effect. Jewish ambassadors were now on their way to Egypt to seek aid against Assyria (Isa 30:2-6, Isa 30:15; Isa 31:1). Isaiah denounces this reliance on Egypt rather than on Jehovah. God had prohibited such alliances with heathen nations, and it was a leading part of Jewish polity that they should be a separate people (Exo 23:32; Deu 7:2). Next: Isaiah Chapter 30