וְאַתָּ֣ה יְ֭הוָה לְעוֹלָ֣ם תֵּשֵׁ֑ב וְ֝זִכְרְךָ֗ לְדֹ֣ר וָדֹֽר׃
But Thou, O LORD, sittest enthroned for ever; and Thy name is unto all generations.
Rashi on Psalms
But You Who will be enthroned forever, and Who swore to us by Yourself, just as You exist, it is incumbent upon You to fulfill it. Therefore...