[It is he] that giveth salvation to kings,.... Which is the reason of singing the new song to the Lord, or this is the matter of it. The Lord is the Preserver of men and beasts, the Saviour of all men, and especially of them that believe; who are in a spiritual sense kings and priests unto God; and in a temporal sense he saves high and low, rich and poor: but there is a particular providence respecting kings; who, as they are the powers ordained of God, and are his vicegerents on earth, and represent him, so they are preserved by him; were they not, there would soon be an end to all public order and government: they cannot save themselves; nor are they saved by their bodyguards about them; nor is any king saved by the multitude of his host, but by the Lord, Ps 33:16.
Or, "he that giveth victory to kings"; over their enemies; which is not obtained by the strength and force of their armies, and by their military skill valour; but by the right hand and arm of the Lord: and therefore, whenever this is the case, a new song should be sung to him; see Ps 98:1.
David no doubt has regard to himself, and to the many salvations God had wrought for him, and the victories he had given him; as also to the King Messiah, whom God heard and helped, as man and Mediator, in the day of salvation, and gave it to him, and in which he rejoiced, Isa 49:8;who delivereth David his servant from the hurtful sword; David literally, the servant of the Lord by creation, redemption, and grace, as well as by his office, as king of Israel; him the Lord delivered from the sword of Goliath, as the Targum; from the sword of Saul, as Jarchi and Kimchi; and from the sword of strange children, as Arama; of all his enemies he had been or was engaged with in war: and David mystically, Christ the son of David, God's righteous servant, he chose, called, upheld; and in whom he was glorified, by doing his work diligently, faithfully, and completely; him he delivered from the sword of justice, when he had satisfied it; and from wicked men, like a sword; and from all his enemies, and death itself, when he raised him from the dead, and gave him glory; see Ps 22:20.