וְלֹֽא־אָבָ֤ה יְהוָה֙ לְהַשְׁחִ֣ית אֶת־יְהוּדָ֔ה לְמַ֖עַן דָּוִ֣ד עַבְדּ֑וֹ כַּאֲשֶׁ֣ר אָֽמַר־ל֗וֹ לָתֵ֨ת ל֥וֹ נִ֛יר לְבָנָ֖יו כָּל־הַיָּמִֽים׃
Howbeit the LORD would not destroy Judah, for David His servant’s sake, as He promised him to give unto him a lamp and to his children alway.
Read midrashic interpretation of II Kings 8:19: and classical rabbinic exegesis.