Contrary to what many think, we have to make judgments about others on a routine basis. Jesus both models and teaches how we can determine the people we want as our friends and the ones to keep at arms length.
33 Make a tree good and its fruit will be good, or make a tree bad and its fruit will be bad, for a tree is recognized by its fruit. 34 You brood of vipers, how can you who are evil say anything good? For the mouth speaks what the heart is full of. 35 A good man brings good things out of the good stored up in him, and an evil man brings evil things out of the evil stored up in him.
List the metaphors you see in this short passage?
Matthew 12:33 is one of the most difficult to understand in Matthews Gospel, particularly because most of our English versions fail to make its original meaning clear. We will take a closer look.
My rough translation: Either take as an example that a tree is good, and so its fruit is good. Or take as an example that a tree is rotten, and so its fruit is rotten. Because it is from its fruit that a tree can be understood. (Matthew 12:33).
My paraphrase: If you want to understand the quality of a tree, start with its fruit. Good fruit means that the tree is good. Rotten fruit means that the tree is rotten. (Matthew 12:33).
After producing my analysis above, I discovered the following translation (or paraphrase) of verse 33 from the New Living Translation: A tree is identified by its fruit. If a tree is good, its fruit will be good. If a tree is bad, its fruit will be bad. This shows once again that NLT tends to shine when idioms are being used by the authors of the New Testament books.
This understanding of verse 33 may be confirmed from the context. Jesus has been healing people and casting out demons. Everyone understands that these acts are good, approved by God, as is shown by their pensive question, Could this be the Son of David [the Messiah]? (Matthew 12:23).
That question shows that the people who saw Jesus work his miracles of healing and exorcism understand those deeds to be good, and so they take the person doing the deeds to be good. They are judging Jesus by his fruit. However, the Pharisees are trying to confuse everyone by saying that Jesus works his miracles using Satans power (Matthew 12:24). With their spiritual authority, they are trying to sell the idea that it was a rotten tree that produced this good fruit.
How does this exchange demonstrate that we must judge religious authorities?
When we get to verse 33, Jesus is reminding the crowd of the right way to judge a tree, and that is by the quality of the fruit.
Having shown that the Pharisees are guilty of such intentional evil that they cannot be forgiven, Jesus adopts a metaphor for them that John had used: You brood of vipers (verse 34a). As vipers, their mouths contain poison! The lies they have told about Jesus come from evil hearts, just as the rhetorical question in verse 34a suggests.
When we get to verse 35, the metaphor seems to change to viewing the heart as a well and the words from the Pharisees mouths as the overflow from their innermost self, their heart. Jesus has already said that they are evil, so their poisonous words make a consistent picture. Small wonder that people would stay clear of them.
In verse 35, Jesus contrasts two kinds of people using the metaphor of a treasure house. This verse has two instances of the Greek verb ekballo that we have previously seen with the meaning cast out or drive out in relation to demons driven out of a person by Jesus. Here ekballo occurs with the meaning bring forth and represents the actions taken by the person themselves. The good man brings forth good treasures, while the evil man brings forth evil treasures. Imagine a Christian showing kindness to another person, or a terrorist killing them without an editing thought.
Verse 35 begs the question: what kind of treasures are you storing? Have your treasures changed quality since you gave your allegiance to Jesus Christ? Explain.
You can see that Jesus has used the metaphors of the tree, the well and the treasure house to say that what is in the heart will emerge to be seen by others, especially God. People can only see our deeds and our words, but God knows our hearts and everything that emerges from them!
 BDAG-3, poieo, take as an example (meaning 5.b.); kai, and so (meaning 1.c.), q.v.