Reprobation Across the Scriptures: Moses to Jesus

In a brief pericope, Jesus says something shocking: "Either make the tree good and its fruit good, or make the tree bad and its fruit bad, for the tree is known by its fruit. You brood of vipers! How can you speak good, when you are evil? For out of the abundance of the heart the mouth speaks. The good person out of his good treasure brings forth good, and the evil person out of his evil treasure brings forth evil. I tell you, on the day of judgment people will give account for every careless word they speak, for by your words you will be justified, and by your words you will be condemned" (Matthew 12:33-37). The shocking thing is to see the Lord Jesus calling people "brood of vipers," not at all the kind of language which we would expect from the effeminate Jesus of popular Christianity. The same phrase is used for the same people by John the Baptist in Matthew 3:7, and a second time by Jesus in Matthew 23:33. 
 

John the Baptist Preaches

When certain words are repeated by two different biblical figures, especially when one is Jesus, and in different circumstances, it should be taken as an indication that they have special significance. What might it be here?

I think the key is the very first declaration of the Gospel in the Bible (Genesis 3:15): "I will put enmity between you and the woman, and between your offspring and her offspring; he shall bruise your head, and you shall bruise his heel." While lacking the clarity that would come with later revelation, we see the distinction between the elect, "the seed of the woman," and the reprobate, "the seed of the serpent." 

Look at that second phrase. Do you see the parallel? Are not "brood of vipers" and "seed of the serpent" equivalent? I think that they are. 

Jesus is demonstrating His omniscience in declaring some of those around Him to be reprobates, to be destined from prehistory to follow Satan, and to be under the judgment of God (compare I Peter 2:8). John the Baptist was not omniscient, of course, but appears to have received special insight to recognize the same thing. They both borrow an image from Moses to address a similar spiritual situation, in which wicked people are demonstrating to which division of humanity they belong.