Outline:

1. Summons to praise
2ab. Rationale: God’s kindness and faithfulness has been shown in the past and will continue forever.
2c. Summons to praise

This is the shortest psalm in the psalter, and the question arises, “Is Ps. 117 its own entity or part of another psalm?” Based on the fact that Ps. 117 is given an individual chapter in both the MT and the LXX, and that it contains the standard summons to praise (v.1) and the introductory ki (v.2), Gerstenberger feels the psalm is its own entity. For support he points to two short songs that stand alone: Miriam’s song at the sea (Ex. 15:21) and the humorous song of the Israelite women (1Sam 18:7). Yet, due to the fact that “summons to praise” are attached to other genres as well, scholars as early as Gunkel have speculated that Ps. 117 is an addendum to Ps. 116.

Psalm 117 fits into the genre of Hymns. It calls on “the nations” to praise (v.1) because God has and will continue to show Israel His kindness and faithfulness (chesed and ‘emet, see Ex. 34:6). While it is possible this Psalm was said in the presence of gentiles, it is likely that v.1 is rhetorical. For instance, see Isa. 44:23 which has the same structure as Ps. 117 and has a rhetorical summons to praise: “Shout, O heavens, for the LORD has acted; Shout aloud, O depths of the earth! Shout for joy, O mountains, O forests with all your trees! For the LORD has redeemed Jacob, Has glorified Himself through Israel.”