Earthly riches do not last nor do they have any eternal value. James speaks of these events as if they had already happened. Alternate translation: "Your riches will rot, and your clothes will be eaten by moths. Your gold and silver will become tarnished" (See: [[rc://en/ta/man/translate/figs-pastforfuture]])
These phrases are used here to describe how gold and silver are ruined. Alternate translation: "are ruined ... their ruined condition" or "are corroded ... their corrosion"