WEB
Now therefore, may Yahweh, the God of Israel, keep with your servant David my father that which you have promised him, saying, ‘There shall not fail you a man in my sight to sit on the throne of Israel, if only your children take heed to their way, to walk before me as you have walked before me.’
YLT
‘And now, Jehovah, God of Israel, keep for Thy servant David my father that which Thou spakest to him, saying, There is not cut off to thee a man from before Me, sitting on the throne of Israel—only, if thy sons watch their way, to walk before Me as thou hast walked before Me.