John was not asking for information. He was questioning whether these men truly understood why they had come. Barnes says John expressed his astonishment that men so hardened and hypocritical had been moved to flee from the coming wrath. Gill suggests what drew them: John had gained a great name among the people as a holy man, and they wished to be thought holy too. John's next words show his concern. He tells them to "bring forth therefore fruits meet for repentance" and not to say, "We have Abraham to our father" (Matthew 3:8-9). The question presses them to ask whether they came to repent, or only to add one more religious act to their record.

The Pharisees and Sadducees give no recorded reply. John answers the question's challenge himself by calling for real change: "Bring forth therefore fruits meet for repentance" (Matthew 3:8). He warns that family descent from Abraham will not save them, for "God is able of these stones to raise up children unto Abraham" (Matthew 3:9), and that "the axe is laid unto the root of the trees" (Matthew 3:10). He then points beyond himself to the One coming after him who "shall baptize you with the Holy Ghost, and with fire" (Matthew 3:11-12).

The Pharisees and Sadducees were the two leading religious parties of the day. Barnes describes the Pharisees as the most numerous and wealthy sect, known for strict outward religion, and the Sadducees as fewer but wealthy, rejecting the resurrection, angels, and spirits (Matthew 22:23; Acts 23:8).

"Generation of vipers" is gennemata echidnon in Greek, literally "offspring of vipers." Barnes thinks the image is "probably" used "to denote their malignancy and wickedness." Gill notes that the viper looks beautiful outwardly but is "full of poison," a picture of hypocrisy. The word "warned" (hupedeixen) means to show or point out. "The wrath to come" uses a word meaning "about to come." Commentators read it differently. Barnes takes it as "the Divine indignation, or the punishment that will come on the guilty." Gill limits it to "temporal calamity and destruction," the judgment that soon fell on that nation. Either way, John speaks of real judgment that is near.

John's question shows that God cares about the heart behind religious acts. Baptism was a sign of repentance, with people "confessing their sins" (Matthew 3:6). Coming to the water without a changed life missed the point. God does not need anyone's family line to keep His promises: He can raise up children to Abraham from stones (Matthew 3:9).

Yet the warning itself is a mercy. John warns of wrath so that people will flee it, and he points to the One coming after him (Matthew 3:11). Jesus would later use the same words, "generation of vipers," with the Pharisees (Matthew 12:34; Matthew 23:33). Paul later describes Jesus as the one "which delivered us from the wrath to come" (1 Thessalonians 1:10).