Isaiah 36-37 records Yahweh’s judicial deliverance (37:7, 29, 36) of His people, Judah, from the blasphemous assault of the Assyrians. The importance of the deliverance recorded in this account is confirmed by the lengthy records of it in two other books of the Old Testament (2 Kings 18:13-19:37 and 2 Chron. 32:1-23).
Faced with a humanly insurmountable opponent that reproached Yahweh as being incapable of deliverance, King Hezekiah (37:14-20) and Isaiah (cf. 2 Chron. 32:20) prayed to Yahweh. They requested that Yahweh rebuke the arrogant assertions of the Assyrians (37:29), who blasphemed Yahweh as being even less capable of deliverance (2 Chron. 32:15) than the deities of the peoples they had already conquered (36:13-20). They requested His deliverance from the hand of the king of Assyria so that all the kingdoms of the world would know that He alone is the Lord (37:20).
In response to their prayers, Yahweh promised to defend Jerusalem and to deliver it for His own sake and for the sake of His servant David (37:21, 33-35). Yahweh’s promise made no mention of His use of any agent (37:35). The account of the actual deliverance, however, states, “Then the angel of the Lord went out, and struck 185,000 in the camp of the Assyrians; and when men arose early in the morning, behold, all of these were dead” (37:36), indicating that part of the judgment that Yahweh promised He would render was actually carried out by the Angel of the Lord.
Unlike Isaiah 37 and 2 Kings 19, the parallel account in 2 Chronicles 32 does not record Yahweh’s promise of deliverance. In addition, it differs from the other accounts by specifying that ”the Lord sent an angel who destroyed every mighty warrior, commander and officer in the camp of Assyria” (32:21).
This version of the account explicitly states that the angel was sent by Yahweh to judge for Him. The chronicler adds, “So the Lord saved Hezekiah and the inhabitants of Jerusalem from the hand of Sennacherib the king of Assyria” (32:22a). Because the Lord delivered them from the Assyrians through the destruction that was effected by the angel whom He sent (32:21), these verses show that He saved them through the work of the angel as His judicial agent.
The account of Yahweh’s deliverance of Hezekiah, including the significant variation between Isaiah 37 and 2 Chronicles 32, has important bearing on the assessment of passages that do not explicitly speak either of Christ’s judging or of His judging as God’s judicial agent in contexts that were originally spoken of as judgment that Yahweh promised to execute (See, for example, Acts 3 and 7 compared with Deuteronomy 18). It shows that understanding Christ’s judging for God in such passages despite an explicit statement to that effect is biblically based (cf. 2 Sam. 24:12-13 with 24:15-16; John 5:22).
It also shows the vital link between God’s promise of deliverance for His people who trust in Him and Christ’s judicial work for God. As the Angel of the Lord, He was God’s judicial executor who both saved God’s people and destroyed their enemies.
 The parallel account in 2 Kings 19 is worded similarly to Isaiah’s: “Then it happened that night that the angel of the Lord went out and struck 185,000 in the camp of the Assyrians; and when men rose early in the morning, behold, all of them were dead” (2 Kings 19:35). Young comments on Isaiah 37:36, “He who went out was an angel belonging to Yahweh, the God of Israel. The phrase is not a substitute for Yahweh himself, nor does it simply designate a messenger, but an angel. The language calls to mind the destroying angel of Exodus 12:12, 13, 23, and of 2 Samuel 24:1, 15, 16. Emphasis in all these passages falls upon the Lord as causing the destruction; and yet He does this through His angel, whom He sends for this purpose.” Edward J. Young, The Book of Isaiah (Grand Rapids: Wm. B. Eerdmans Publishing Co., 1969), 2:504.
 While the angel of the Lord slew the multitude of the Assyrians (37:36), Sennacherib’s sons “killed him with the sword” (37:38).