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 a tree is good, it will have good fruit, and if a tree is bad, it will have bad fruit." This was a proverb. People were to apply its truth to how they can know whether a person is good or bad.
This can be translated in active form. Alternate translation: "people recognize a tree by its fruit" or "people know whether a tree is good or bad by looking at its fruit" (See: [[rc://en/ta/man/jit/figs-activepassive]] and [[rc://en/ta/man/jit/figs-metaphor]])