Psalms - Chapter 115
Wait... Is It His or Ours?
David says that G-d should not redeem the nation because they deserve it, but for the sake of His own Name, so that it should be sanctified among the nations. David asks that G-d not give the nations the opportunity to question His whereabouts, when He is in Heaven above and His will is executed on Earth below.
Other nations worship man-made idols that may have mouths, eyes, ears, and other bodily parts, but they have no senses and they cannot take any action. Those who worship them should become like them! (Man is in the image of G-d; those who worship idols might as well be in the image of their "gods!")
David says that the Jewish people trusts in G-d, who is their help and their shield. The Kohanim, descendants of Aaron, likewise trust in G-d, serving Him at all times. All those who are in proper awe of G-d place their trust in Him. (This last group may refer to G-d-fearing non-Jews or converts; see Rashi and Radak.)
G-d has remembered us, David says, and He will bless those groups that put their trust in Him: the Jews, the Kohanim, and the G-d-fearing of the nations, both small and great. David prays that G-d cause his adherents and their children to enjoy abundance. They are blessed by the only One who can truly bestow blessing, since He created Heaven and Earth.
The Heavens are G-d's exclusive domain, but He has given man a measure of control over the Earth. A person who is oblivious to G-d is like the dead - unable to praise G-d. The righteous, however, will bless G-d now and forevermore.
The Talmud in Brachos (35a) cross-references verse 16 of this Psalm ("the Earth He has given to human beings") with a verse in Psalm 24 ("the Earth and everything in it belongs to G-d"). The Talmud concludes that before we say a blessing over something G-d has created, it is exclusively His. After we say a blessing, He grants us the right to partake.
This Psalm is divided into two sections in Hallel. The first, "Lo Lanu," is omitted in the "half Hallel." (The second, "Yevareich es Beis Yisroel," is always recited.)