en_tn_condensed/isa/03/10.md

Tell the righteous person that it will be well

"Tell the one who is doing what is right that I will make things good for him"

the righteous person

This refers to righteous people in general. Alternate translation: "righteous people" (See: rc://en/ta/man/jit/figs-genericnoun)

for they will eat the fruit of their deeds

Deeds are spoken of as if they were trees giving fruit that can be eaten. The fruit stands for the reward for doing good deeds. Alternate translation: "for they will receive their reward for their good deeds" or "for they will receive their reward for the good things they have done" (See: rc://en/ta/man/jit/figs-metaphor)

they will eat the fruit of their deeds

The Hebrew text has these plural pronouns here, but they refer to any righteous person. Translators can choose to translate them as singular: "he will eat the fruit of his deeds."