Possible meanings are 1) "If you make a tree good, its fruit will be good, and if you make the tree bad, its fruit will be bad" or 2) "If you consider a tree to be good, it is because its fruit is good, and if you consider a tree to be bad, it is because its fruit is bad." This was a proverb. People were to apply its truth to how they can know whether a person is good or bad.
The words "tree" and "fruit" are metaphors for a person and his deeds, respectively. This can be translated in active form. Alternate translation: "people recognize trees by their fruit" or "people know whether a person is good or bad by looking at the results of that person's activities" (See: [[rc://en/ta/man/jit/figs-activepassive]] and [[rc://en/ta/man/jit/figs-metaphor]])