Yahwe will increase you,
You and your children.
Blessed are ye of Yahwe,
Maker of heaven and earth.
Finally where in verses 16-18 would ordinarily be expected a renewed call to praise, we have here something that resembles the vow of a prayer of petition, although it is hymnal to the extent that it promises to praise Yahwe for evermore.
It ought also to be observed that the psalm has a number of features that indicate it to be liturgical in character. Verses 1-8, it may be supposed, were sung by the congregation made up of Israelites, and proselytes, led by priests and Levites. Then verses 9-11 constitute an antiphonal response to their petition, one choir singing: “O Israel, trust in Yahwe,” while the second choir responded: “He is their help and their shield.” The whole congregation that first sang verses 1-8 now sings verses 12-13, and in reply to their affirmation of faith, the temple choir gives the comforting assurance of Yahwe’s favor in verses 14-15. Then the congregation sings the hymnal vow of verses 16-18. It remains accordingly a question whether we have in Psalm 115 a liturgical hymn of praise, or a liturgical psalm of petition in which the hymnal spirit and form has a prominent place.
Psalm 33 is also difficult of classification. Verses 1-3 are a typical hymnal call to praise and verses 4-7 give customary reasons for praising Yahwe. Then verse 8 issues a renewed call to worship Yahwe and verses 9-11 again give customary reasons for so doing. But when we arrive at verse 12 we have the characteristic introduction to a wisdom psalm:
Happy the nation whose God is Yahwe,
The people he hath chosen for his inheritance.
and there follow in verses 13-19 the sententious utterances, characteristic of the wisdom literature, teaching that neither men nor nations are saved by physical might, but only by the mercy of Yahwe extended to those who fear him. Not inappropriately there follows, in verses 20 and 21, an affirmation of faith in Yahwe, which is followed in turn by the brief petition: