51. Tower of salvation. Ps. 18:50 reads: “Great deliverance giveth he to his king.” The meaning is clear: the Lord bestows the fullness of His salvation upon the king, granting to him ever greater triumphs over his enemies.
To his seed. There seems to be a reference to the prophecy of Nathan in 7:12-16, that after David fell asleep the Lord would set up his seed after him and establish the throne of his kingdom forever. For this great mercy David is now thanking the Lord. The whole psalm is a grand anthem of praise and thanksgiving, a beautiful and heartfelt expression of David’s confidence in God and of his grateful acceptance of the Lord’s assurance that He would give the kingdom to him and to his seed forever.
1. The last words of David. This chapter consists of two distinct parts. Verses 1-7 are a psalm that constitutes the last formal utterance of David, and 8-39 are a list of his heroes. The song is not found in the book of Psalms.
Said. ne’um, a divine utterance either directly by God or through His prophets. The word is not used to designate ordinary human speech. It occurs most frequently in the phrase “saith the Lord.” False prophets used the word in order to make it appear that they were giving divine messages (Jer. 23:31).
Raised up on high. David was a man of humble beginnings whom the Lord chose and raised to his lofty position as prophet and king (see 2 Sam. 7:8, 9; Ps. 78:70; 89:27).
Sweet psalmist of Israel. These words are a fitting description of the man who wrote not only this song but also many psalms that have proved an inspiration to men of all ages.