V.7-36 These words are also found in a number of different Psalms. But God has a purpose in putting them here and in this order. It is a song of rejoicing It all leads up to the Lord reigning as King (v. 31). David has been set up as king. The promises made to Abraham long before, are all going to be fulfilled when Christ reigns as King. It is not so much as Priest, but as King. We have noticed in the chapters we have been reading, that the king does all the appointing. The king is the prominent person. So it shall be in the millennium. Christ the King shall lead all the praise to God.
V.37-43 The ark is in Jerusalem, but the altar and the priests are still at Gibeon.
V.39-40 God was setting that place aside because the priests had failed.