“Beware of false prophets, who come to you in sheep’s clothing but inwardly are ravenous wolves. You will know them by their fruits. Are grapes gathered from thorns, or figs from thistles? In the same way, every good tree bears good fruit, but the bad tree bears bad fruit. A good tree cannot bear bad fruit, nor can a bad tree bear good fruit. Every tree that does not bear good fruit is cut down and thrown into the fire. Thus you will know them by their fruits.”
This should immediately remind us of John the Baptizers words at the beginning of Matthew’s story, “Even now the ax is lying at the root of the trees; every tree therefore that does not bear good fruit is cut down and thrown into the fire” (3:10). Back then we pointed out that this agricultural metaphor would have hit home with Mediterranean Jewish peasants in the first century (or so). We also mentioned that the separation we have made between faith and works is not inherent in the Bible’s worldview. The two things go absolutely together.
What does Jesus add to this theme here? Well, this text is a warning concerning false prophets. John was a prophet who was calling people to a baptism of repentance, asking them to change the way they were living their lives (not subscribe to any particular doctrine). Here Jesus reverses things and says, “Watch out for prophets who are not like John, false ones.” These guys are compared to thorns and thistles. Jesus asks a rhetorical question that is obviously ridiculous. Plants with thorns and thistles produce pain and injury, not fruit that nourishes and pleases. He also calls them wolves in sheep’s clothing (so that’s where that comes from!). Obviously the point is they are disguised as one of you, but in reality they are predators, looking to do you harm.
The point of John’s passage on fruit is that we must “bear fruit worthy of repentance” (3:8). It is targeted at our own inner life and how it relates to those around us. Here Jesus warns us to be on the lookout for the fruit of others. This is a difficult line to walk, because elsewhere we are warned to “Do not judge so that you will not be judged” (7:1). How do these two square with each other?
This probably deserves a more lengthy treatment, but let me try. The difference it seems is in both the intention of the one judging and the relationship to the one being judged. In 7:1-5 Jesus is talking about people who go around pointing out the flaws in others in order to avoid dealing with their own problems. This person needs to refrain from judging others and take care of their own problems first. In 7:15-20 there is a threat from these “ravenous wolves.” Judgment is needed to prevent harm coming to the person. Therefore they need some way of discerning whether someone will lead them astray or harm them in some way.
The answer is to see what kind of tree they are. Usually people say, “Look at their fruits.” Jesus is saying their fruits might look nice (sheep’s clothing, grapes, figs), but it’s a trick if they aren’t a fruit tree (wolf, thistle, thorn).
To tie this in to our current situation, we should consider what kind of “fruits” the industrial food system bears versus alternative methods and systems. We just might find that Monsanto is a false prophet.