(11) Sweareth by him.--This is explained as meaning, "swear allegiance to him as the king," on the analogy of Zephaniah 1:5. And this suits the context. On the other hand, the natural way to understand the phrase, "swear by" or "in him," is to refer it to the only oath allowed to the Israelite," by the name of Jehovah" (Deuteronomy 6:13; Isaiah 65:16; comp. Amos 8:14), in which case we must explain by Deuteronomy 10:20-21, "Swear by his (Jehovah's) name; He is thy praise." Those who are loyal to Jehovah, who appeal to Him in all troubles, will find this promise true, "They shall glory," while the unfaithful and false, not daring to make the solemn appeal, will have their mouth stopped. (Comp. Romans 3:19.)

Verse 11. - But the king shall rejoice in God. The "king," thus suddenly introduced, cannot be an entirely new personage, unknown to the rest of the psalm, and, therefore, must be the composer, speaking of himself in the third person (comp. Psalm 18:50; Psalm 72:1). Every one that sweareth by him (i.e. by God) shall glory; or, shall triumph (Kay). Those who swear by the Name of God show themselves to be believers in God, and will be upheld by him in time of danger (see Deuteronomy 6:13; Isaiah 65:16). But the mouth of them that speak lies shall be stopped. (On the falsehoods told by David's enemies, see 2 Samuel 15:3; 2 Samuel 16:7, 8; and comp. Psalm 38:12; Psalm 41:5-8.)

63:7-11 True Christians can, in some measure, and at some times, make use of the strong language of David, but too commonly our souls cleave to the dust. Having committed ourselves to God, we must be easy and pleased, and quiet from the fear of evil. Those that follow hard after God, would soon fail, if God's right hand did not uphold them. It is he that strengthens us and comforts us. The psalmist doubts not but that though now sowing in tears, he should reap in joy. Messiah the Prince shall rejoice in God; he is already entered into the joy set before him, and his glory will be completed at his second coming. Blessed Lord, let our desire towards thee increase every hour; let our love be always upon thee; let all our enjoyment be in thee, and all our satisfaction from thee. Be thou all in all to us while we remain in the present wilderness state, and bring us home to the everlasting enjoyment of thee for ever.But the king shall rejoice in God,.... Not Saul, as R. Obadiah; as if David wished him well, and that he might have reason to rejoice in God, though he sought his hurt; which sense is rejected by Abea Ezra: but either David, who speaks of himself as king, being anointed by Samuel, and who, upon the death of Saul, was so in fact; and who rejoiced, not merely at the destruction of his enemies, for he lamented the death of Saul, 2 Samuel 1:17; but in God, in his grace and goodness to him, and in his power and justice shown in the vengeance taken on them. Or rather, the King Messiah, who rejoiced in God because of the good of his people, their conversion and salvation, and their deliverance from their enemies, Psalm 21:1;

everyone that sweareth by him shall glory; not by David, though such a form of swearing was used; see 2 Samuel 15:21; or, "to him": and so describes his faithful subjects swearing allegiance to him: but rather by the Lord, in whom the king should rejoice; and designs the worshippers of him; swearing by him being sometimes put for the whole worship and service of God, Deuteronomy 6:13. The Heathens used to swear by their deities, and their chief was called Jupiter Horcius, because he presided over oaths (x). Or else that the King Christ should rejoice in God; and intends such as believe in him and confess him; see Isaiah 45:23, compared with Romans 14:11. And every such an one will glory, not in themselves, nor in anything of theirs, but in Christ, in his grace and righteousness, and in what he is unto them;

but the mouth of them that speak lies shall be stopped; such as Saul's courtiers, who invented and spread lies of David; but now upon the death of Saul, and David's advancement to the throne, would be silent; their mouths being stopped either by death, or through fear: and so all the followers of antichrist, that make and believe a lie, will have their mouths stopped, when cast into the lake of fire, Revelation 21:8.

(x) Euripidis Medea, v. 170. Vid. Alex. ab Alex. Genial. Dier. l. 5. c. 10.