וְֽצַדִּיקִ֗ים יִשְׂמְח֣וּ יַֽ֭עַלְצוּ לִפְנֵ֥י אֱלֹהִ֗ים וְיָשִׂ֥ישׂוּ בְשִׂמְחָֽה׃
But let the righteous be glad, let them exult before God; Yea, let them rejoice with gladness.
Rashi on Psalms
and they will delight with joy And this is the joy, and so will they say, “Sing to God, etc.”