הָקֵ֣ם לְ֭עַבְדְּךָ אִמְרָתֶ֑ךָ אֲ֝שֶׁ֗ר לְיִרְאָתֶֽךָ׃
Bestätige deinem Knecht deine Verheißung, dass er dich fürchte.
Rashi on Psalms
Fulfill for Your servant Your word that You promised me.
Rashi on Psalms
that is for Your fear That I and my children shall fear Your name, for on that condition You promised me (I Kings 2:4): “if your children take heed in their way, etc.”