Albert Barnes Commentary Psalms 98:9

"Before Jehovah; for he cometh to judge the earth: He will judge the world with righteousness, And the peoples with equity." — Psalms 98:9 (ASV)

Before the Lord, for he comes to judge the earth ... - This verse is essentially the same as Psalms 96:13. See the notes at that verse.

The psalm calls for universal praise. The very “reading” of the psalm—so joyous, so jubilant, so animated, so exulting—is suited to awaken the mind to praise, to rouse it to thankfulness, and to fill it with joy.

One cannot read the psalm without being a happier man; without being lifted above the world; without lofty views of God; without a feeling that he is worthy of this universal praise; without recognizing that we are in a world where the mind should be joyful; that we are under the dominion of a God whose reign should fill the mind with gladness.