John the baptist, who said that part ( Not John the apostle of the GOJ) was very much a "fire and brimstone" kind of guy, I can see him saying that.
Now, John Zebedee, the Gospel writer, says over and over that God is love, and merciful and kind, so how do we reconcile this?
Is God loving only IF we put faith in Jesus and those that don't will be struck by his wrath?
Or do we see this as John the Baptist preaching in his strong and in-your-face style that he was known for?
Either way, was John right? will those that don't accept Jesus and put faith in Jesus, suffer God's wrath?
You will notice then in ALL of the GOJ, wrath only appears HERE and nowehere else, maybe that means soemthing...
No one is saying that John was not inspired bt God to deliver God message of repentance, but God does NOT control the voice of those delivering the message.
Just food for thought.