John Gill Commentary Psalms 9:8

"And he will judge the world in righteousness, He will minister judgment to the peoples in uprightness." — Psalms 9:8 (ASV)

And he shall judge the world in righteousness
The word (lbt) , rendered "world", is, as Ben Melech well observes, a general name for all the countries of the habitable world; and so shows that it is the universal judgment that is here spoken of; and which will be carried on and finished with the utmost righteousness, and according to the strictest rules of justice and equity; and is therefore called the righteous judgment of God, (Romans 2:5) ; see (Psalms 96:13) (98:9) (Acts 17:31) ;

he shall minister judgment to the people in uprightness ;
which signifies the same with the former clause, unless by the "world" there, should be meant the wicked of the world; and by the "people" here, the people of God; to whom the righteous Judge will give the crown of righteousness.