In verses 10-13 the psalm closes with an exhortation for all creation, human and nonhuman, animate and inanimate, to worship and praise the universal LORD.

The command Say is apparently addressed to the worshipers. In the context of communicating a message to someone, “Tell” in English would be more appropriate. The message The LORD reigns is to be proclaimed to the nations. The contents of the message in verse 10a-b are phrased in language used in 93.1a, c (which see). And in verse 10c judge … with equity uses the same terms as in 9.8b.

Quoted with permission from Bratcher, Robert G. and Reyburn, William D. A Handbook on the Book of Psalms. (UBS Helps for Translators). New York: UBS, 1991. For this and other handbooks for translators see here .