Charles Ellicott Commentary 2 Kings 8:19

"Howbeit Jehovah would not destroy Judah, for David his servant`s sake, as he promised him to give unto him a lamp for his children alway." — 2 Kings 8:19 (ASV)

To give him always a light. —Compare 1 Kings 15:4; 1 Kings 11:36; and for the promise to David, 2 Samuel 7:12–16.

And to his children. —The reading of many Hebrew manuscripts, the Septuagint, Vulgate, and Targum. Thenius calls this a reading devised for the removal of a difficulty, and asserts that the promise was made to David alone. He would omit the conjunction, and render, “To give him always a lamp in respect of (i.e., through) his sons” (see 2 Chronicles 21:7, Note). Keil adopts the same reading, but translates, “To give him, that is, his sons, a lamp,” making “to his sons” an explanatory apposition.