Isaiah’s ministry covered a span of approximately 60 years. During his lifetime, Isaiah experienced what could be considered the best and worst times in Jerusalem’s history. During King Uzziah’s reign (792 B.C. – 740 B.C.), Judah’s powerful army of over 300,000 men expanded his kingdom’s borders and fortified the city of Jerusalem, making it a secure fortress that could withstand a long siege of enemy attack (2 Kings 16:5). Within a decade of Uzziah’s death, his grandson, king Ahaz cooperated with the Assyrians to defeat the northern kingdom of Israel and erected an altar in the temple of God so he could worship a Syrian god instead (2 Kings 16:15).
Isaiah confronted Ahaz in a location referred to as “the conduit of the upper pool in the highway of the fuller’s field” (Isaiah 7:3). Isaiah told the king of Judah, “The LORD shall bring upon thee, and upon thy people, and upon thy father’s house, days that have not come, from the day that Ephraim departed from Judah” (Isaiah 7:17). Ahaz ignored Isaiah’s warning, no doubt thinking an alliance with the king of Assyria would prevent him from attacking Jerusalem.
Isaiah recorded his prophecy about the king of Assyria as a testimony against king Ahaz and all who doubted God’s intention to punish Judah for its rebellion against him (Isaiah 8:7-8). Later, Isaiah added that Assyria would be destroyed after God was finished using them to punish Samaria and Jerusalem for their idolatry (Isaiah 10:12). Predicting specific details of the Assyrian attack, Isaiah showed the king of Judah that God controlled his kingdom and could give it to whomever he wished (Isaiah 22:20-25).
When Ahaz’s son Hezekiah took over as king in 715 B.C., Israel had already been taken into captivity and the king of Assyria was breathing down Judah’s neck. Isaiah’s message to Hezekiah made it clear that Assyria was doomed and Jerusalem would be spared from destruction (Isaiah 29:22; 30:31). Isaiah warned Hezekiah to not trust in Egypt, but to rely on the LORD. Isaiah stated, “So shall the LORD of hosts come down to fight for mount Zion, and for the hill thereof. As birds flying, so will the LORD of hosts defend Jerusalem, defending also he will deliver it and passing over he will preserve it” (Isaiah 31:4-5).
The moment of truth came in 701 B.C. when “Sennacherib king of Assyria came up against all the defenced cities of Judah, and took them” (Isaiah 36:1). The king of Assyria sent a messenger to Hezekiah with a great army, “And he stood by the conduit of the upper pool in the highway of the fuller’s field” (Isaiah 36:2), the exact location where Hezekiah’s father had first been warned by Isaiah of an Assyrian attack against Jerusalem (Isaiah 7:3,17). Sennacherib claimed to be on a mission from God. He told Hezekiah’s men, “And am I now come up without the LORD against this land to destroy it? the LORD said unto me, Go up against this land, and destroy it” (Isaiah 36:10).