Charles Ellicott Commentary 2 Kings 19:8

"So Rabshakeh returned, and found the king of Assyria warring against Libnah; for he had heard that he was departed from Lachish." — 2 Kings 19:8 (ASV)

So Rab-shakeh returned. —This takes up the narrative from 2 Kings 18:37. It is not said, but is probably to be understood, that Tartan and Rabsaris and the great host (2 Kings 18:17) departed with him, having been thwarted in their purpose.

Libnah. —See Note on 2 Kings 8:22. The great King had taken Lachish. (See Note on 2 Chronicles 32:9.) Its position is not yet determined. Schrader thinks it may be Tell-es-S â fieh, west of Lachish, and north north-west of Eleutheropolis, in which case Sennacherib had already begun his retreat.