Go forth now to meet Ahaz... — At this crisis the prophet, already recognised as such, and gathering his disciples round him (Isaiah 8:16), is told to deliver a message to the king. He finds him halting between two opinions. He is making a show of resistance, but in reality he is not depending either on the protection of Jehovah, or the courage of his people, but on a plan of his own. Why should he not continue to pay tribute to Assyria, as Uzziah and Menahem (2 Kings 15:19) had done, and write to Tiglath-pileser to attack the territories of the invading kings, as he actually did at a later stage in the war (2 Kings 15:29)?
Thou and Shear-jashub thy son. — Assuming Isaiah 6 to give the first revelation of the idea of the “remnant,” it would follow that the birth of the son whose name (Remnant returns — the return being both literal and spiritual — i.e., “is converted”), embodied a prophecy, must have followed on that revelation, and he was probably, therefore, at the time a stripling of sixteen or eighteen. It may be noted that Isaiah had in the history of Hosea 1:2 the example of a prophet who, as his children were born, gave them names which were terribly or hopefully significant. Each child was, as it were, a sign and portent (Isaiah 8:18). The fact that the mother of his children was herself a prophetess (Isaiah 8:3), sharing his hopes and fears, gives a yet deeper interest to the fact.
At the end of the conduit... — The king was apparently superintending the defensive operations of the siege, probably cutting off the supply of water outside the walls, as Hezekiah afterwards did (2 Chronicles 32:3-4). The “upper pool” has been identified with the Upper Gihon pool (Birket-el-Mamilla) or the “dragon’s well” of Nehemiah 2:13. A lower pool meets us in Isaiah 22:9. The “fuller’s field” was near En-rogelim (Isaiah 36:2; 2 Samuel 17:17).