John Gill Commentary Psalms 96:1

"Oh sing unto Jehovah a new song: Sing unto Jehovah, all the earth." — Psalms 96:1 (ASV)

O sing to the Lord a new song
A famous excellent one, suited to Gospel times, on account of the new benefit and blessing of redemption and salvation lately obtained by the Messiah; which should be sung to him, who is the Lord or Jehovah here designed, by all the redeemed ones, (Revelation 5:9) , (See Gill on Psalms 33:3), the Targum adds, ``sing, you angels on high:''

sing to the Lord all the earth :
not the whole land of Israel only, as Aben Ezra interprets it; though here the Saviour first appeared, taught his doctrines, wrought his miracles, suffered, and died for the salvation of his people; here the angels first began the new song; and here those that believed in him first expressed that spiritual joy which afterwards spread through the whole world, and who are here called upon to sing; namely, all those that are redeemed from among men, throughout all the earth:

believing Gentiles are here intended: the Targum is, ``sing before the Lord, all you righteous of the earth.''