וְלֹֽא־תַכְרִ֧ת אֶֽת־חַסְדְּךָ֛ מֵעִ֥ם בֵּיתִ֖י עַד־עוֹלָ֑ם וְלֹ֗א בְּהַכְרִ֤ת יְהוָה֙ אֶת־אֹיְבֵ֣י דָוִ֔ד אִ֕ישׁ מֵעַ֖ל פְּנֵ֥י הָאֲדָמָֽה׃
but also thou shalt not cut off thy kindness from my house for ever; no, not when the LORD hath cut off the enemies of David every one from the face of the earth.’
Read midrashic interpretation of I Samuel 20:15: and classical rabbinic exegesis.