The Consequence Of God's Judgment On Those Who Rebel Against The King Will Be That The King Will Rejoice In God, And Those Who Are Faithful To Their Oaths Of Loyalty Sworn In God's Name Will Glory (Psalms 63:11).
This final verse fits admirably into the story of the rebellion of Absalom, who by deceit and half truths sought to overthrow David. Deeply aware of how Absalom and his supporters have maligned him, David is confident that their mouths will be stopped, whilst he, the king, being delivered, will rejoice in God, and all his loyal supporters will rejoice with him, and glory in God's deliverance.
‘But the king will rejoice in God,
Every one who swears by him will glory,
For the mouth of those who speak lies,
Will be stopped.'
David has confidence that God will deliver him, with the consequence that he will rejoice in God. Similarly those who have made their oaths of loyalty to him in God's Name, and have abided by them, will have cause to glory, for they will see him vindicated. In contrast, rather than rejoicing and glorying, the mouths of those who speak lies and deceive others will be stopped. They will have no cause to rejoice and glory.
The whole Psalm is a reminder of God's loyalty to those who are loyal to Him. And it is a reminder that just as David's followers were to be loyal to their anointed king, so are we to be loyal to great David's Greater Son, our Lord, Jesus Christ.