At that time Merodach-baladan the son of Baladan, king of Babylon, sent envoys with letters and a present to Hezekiah, for he heard that Hezekiah had been sick.
Here is, I. An embassy sent to Hezekiah by the king of Babylon, to congratulate him on his recovery, Kg2 20:12. The kings of Babylon had hitherto been only deputies and tributaries to the kings of Assyria, and Nineveh was the royal city. We find Babylon subject to the king of Assyria, Kg2 17:24.
Commenting on 2 Kings 20:12-21
And the rest of the acts of Hezekiah, and all his might,.... Which he exerted in his wars with his enemies, and in the reformation of religion, and abolition of idolatry: and how he made a pool, and a conduit, and brought water into the city; at the same time that he cut it off from the enemy without, see Ch2 32:3, are they not...
Berodach-baladan-- (Isa 39:1), the first king of Babylon mentioned in sacred history; formerly its rulers were viceroys of the Assyrian monarchs. This individual threw off the yoke, and asserting his independence, made with varying success, a long and obstinate resistance [RAWLINSON, Outlines]. The message of congratulation to Hezekiah, was, in all likelihood, accompanied with proposals for a defensive alliance against their common Assyrian enemy.