Isaiah ministered during the reigns of four Judean kings (1:1): Uzziah (792-740 B.C.), Jotham (750-732 B.C.), Ahaz (735-715 B.C.), and Hezekiah (715-686 B.C.).11The prophet began his ministry in the year that King Uzziah (or Azariah) died, namely, 740 or 739 B.C. (6:1).
During Uzziah's reign Judah enjoyed peace because of her surrounding nations' lack of antagonism and hostility. However, in 745 B.C. Tiglath-pileser III mounted the throne of Assyria and began to expand his empire. His three successors (Shalmaneser V, Sargon II, and Sennacherib) proved equally ambitious. Aram (Syria) and Israel (Ephraim) felt the pressure of Assyrian expansion before Judah did, but in King Ahaz's reign Judah had to make a crucial decision regarding her relationship to Assyria. Isaiah played a major role in that decision.
A second major crisis arose during the reign of King Hezekiah. By this time Babylon had defeated Assyria, and it was also expanding aggressively in Judah's direction. Again Isaiah played a major part in the decision about how Judah would respond to this threat.
". . . Isaiah exercised his prophetic ministry at a time of unique significance, a time in which it was of utmost importance to realize that salvation could not be obtained by reliance upon man but only from God Himself. For Israel it was the central or pivotal point of history between Moses and Christ. The old world was passing and an entirely new order of things was beginning to make its appearance. Where would Israel stand in that new world? Would she be the true theocracy, the light to lighten the Gentiles, or would she fall into the shadow by turning for help to the nations which were about her?"12
Sennacherib outlived Hezekiah, who died in 686 B.C., and Isaiah recorded the death of Sennacherib in 681 B.C. (37:38). Just how long the prophet ministered after that event is impossible to determine, but he must have prophesied for at least 60 years. However the bulk of the material in his book derives from the first 50 of those years (ca. 740-690 B.C.).
