“A good tree cannot bear bad fruit, and a bad tree cannot bear good fruit” (Matthew 7:18).
Jesus said that good trees are not able to bear bad fruit. If Adam and Eve were created righteous, how could they fall into sin? Ultimately the answer is a mystery. St. Augustine, however, provides some insights into the matter. Today we will study what he wrote about this topic in his valuable little treatise on basic Christian doctrine, The Enchiridion.
Augustine argues that the fact of Adam’s sin is not a violation of Christ’s principle that a good tree cannot bring forth evil fruit. He points out that the context of Jesus’ aphorism is His preceding statement that people cannot gather grapes from thornbushes or figs from thistles because grapes and figs do not grow on such plants (Matthew 7:16). This parable presupposes, argues Augustine, that all four plants (grapes, figs, thorns, and thistles) grow in soil. For these plants to grow, the soil must be good because nothing grows in a pure desert.
Here is how the analogy works out, according to Augustine. The good tree is a good will, and out of a good will only good actions can proceed. Similarly, the bad tree is an evil will, out of which only evil actions proceed. Both the good and the evil wills, however, are attributes of human nature, and human nature, being created by God and in His image, is good. In other words, human nature, as created by God, is good, but as distorted through the willfulness of sin, the human will and actions are bad.
Human beings, thus, are like the soil. They have the potential to produce good or bad trees, with good or bad fruit. Adam was a good soil (Genesis 2:7), but he chose to turn his will into a bad tree and his fruit into bad fruit. As a result, all of his posterity came under the judgment of sin and are born with evil wills that produce corrupt fruit.
The raw material of humanity, however, is still good. The tragedy of sin is that it takes something good—the image of God—and perverts it into something evil. Man takes his good gifts, by which he images God, and through his evil will transforms them into evil actions, just as a bad tree transforms minerals and water into bad fruit.
Augustine is saying that the good tree represents our commitment to take the raw materials God has given us in our soil and transform them into good fruit. What are the raw materials God has given you? What kinds of fruit should you be looking for?