Verses 50, 51. -

"Therefore will I praise thee among the nations,
And to thy Name will I sing.
Great deliverance giveth he to his king,
And showeth grace to his messiah -
To David, and to his seed forever." Great deliverance; literally, he maketh great the salvation of his king; that is, he rescueth him marvellously again and again. The K'ri substitutes tower, but it has no support either from the versions or from Psalm 18, though admitted into the Authorized Version. The difference between the two words "making great" and "tower" is, in the Hebrew, trifling. To his messiah. This mercy was shown to David as the anointed theocratic king, whose rule was the symbol of that of Christ.

22:1-51 David's psalm of thanksgiving. - This chapter is a psalm of praise; we find it afterwards nearly as Ps 18. They that trust God in the way of duty, shall find him a present help in their greatest dangers: David did so. Remarkable preservations should be particularly mentioned in our praises. We shall never be delivered from all enemies till we get to heaven. God will preserve all his people, 2Ti 4:18. Those who receive signal mercies from God, ought to give him the glory. In the day that God delivered David, he sang this song. While the mercy is fresh, and we are most affected with it, let the thank-offering be brought, to be kindled with the fire of that affection. All his joys and hopes close, as all our hopes should do, in the great Redeemer.Therefore I will give thanks unto thee, O Lord, among the heathen, and I will sing praises unto thy name. See Gill on Psalm 18:49.