What Isaiah unfolds, then, is a series of calamities that have overtaken the people of Israel. It is impossible for us to identify every one of them with a particular event in Israel's history otherwise known to us. Some it is not difficult to recognize; but the prophet passes in a perplexing way from Judah to Ephraim and Ephraim to Judah, and in one case, where he represents Samaria as attacked by Syria and the Philistines, he goes back to a period at some distance from his own. There are also passages, as for instance x. 1-4, in which we are unable to decide whether he describes a present punishment or threatens a future one. But his moral purpose, at least, is plain. He will show how often Jehovah has already spoken to His people by calamity, and because they have remained hardened under these warnings, how there now remains possible only the last, worst blow of an Assyrian invasion. Isaiah is justifying his threat of so unprecedented and extreme a punishment for God's people as overthrow by this Northern people, who had just appeared upon Judah's political horizon. God, he tells Israel, has tried everything short of this, and it has failed; now only this remains, and this shall not fail. The prophet's purpose, therefore, being not an accurate historical recital, but moral impressiveness, he gives us a more or less ideal description of former calamities, mentioning only so much as to allow us to recognize here and there that it is actual facts which he uses for his purpose of condemning Israel to captivity, and vindicating Israel's God in bringing that captivity near. The passage thus forms a parallel to that in Amos, with its similar refrain: _Yet ye have not returned unto Me, saith the Lord_ (Amos iv. 6-12), and only goes farther than that earlier prophecy in indicating that the instruments of the Lord's final judgement are to be the Assyrians. Five great calamities, says Isaiah, have fallen on Israel and left them hardened: 1st, earthquake (v. 25); 2nd, loss of territory (ix. 8-12); 3rd, war and a decisive defeat (ix. 13-17); 4th, internal anarchy (ix. 18-21); 5th, the near prospect of captivity (x. 1-4). 1. THE EARTHQUAKE (v. 25).--Amos closes his series with an earthquake; Isaiah begins with one. It may be the same convulsion they describe, or may not. Although the skirts of Palestine both to the east and west frequently tremble to these disturbances, an earthquake in Palestine itself, up on the high central ridge of the land, is very rare. Isaiah vividly describes its awful simplicity and suddenness. _The Lord stretched forth His hand and smote, and the hills shook, and their carcases were like offal in the midst of the streets._ More words are not needed, because there was nothing more to describe. The Lord lifted His hand; the hills seemed for a moment to topple over, and when the living recovered from the shock there lay the dead, flung like refuse about the streets.