What is essential and truly preparatory to Jesus’ proclamation of good news is John’s summons to conversion of heart. The “way” that Isaiah wanted prepared in the wilderness is one that must be prepared in the wilderness of the human heart. The good news will then find a hearing when at last it is proclaimed. The greatest obstacle to conversion of heart is complacency – a complacency that especially stems from privileged status and a sense that one is different from the despised outsiders and so can rest secure. Jesus will “baptise with the Holy Spirit and with fire”. That is, he will seek to catch up human lives into the fire that is God’s love, communicated through the Spirit. But only hearts that are truly repentant and converted will be able to be grasped within a “baptism” of this kind. John’s baptism with water is a preparatory rite of conversion, readying human hearts for the entrance of this message about God’s love, the true “knowledge of the Lord” that Jesus will impart.