NOTES for Luk 3:10
Those who came to John were not asking by chance what they should do next. John was speaking of the Messiah's imminent coming. In Judea at that time many, if not all, were awaiting the Messiah. And many were sure they were ready to meet Him. There were even more who were not sure they were ready, but were sure they knew how to prepare. And most were sure that the Messiah's coming would be a feast for them, a feast of meeting God's Servant and a feast of the triumph of the Kingdom whose inhabitants they hoped to become.
And then a prophet appears who says that it is not all so simple. That the meeting may turn out to be not so joyful at all. That in essence there are practically no people ready for this meeting. And that very many, if not all, who await the meeting with the Messiah will have to prepare. In such a situation the question of what to do, how to prepare, was entirely urgent. John spoke of conversion and purification. He spoke of them even to those who, in general, had no special reason to consider themselves unclean. He spoke to those who already believed in the God of Israel. What more is needed?
Conversion implied some changes in life. What changes? Those who came to John and believed him were asking him precisely this. The prophet spoke of fiery purification, and his listeners understood what he meant. Theophany can become a consuming fire for a person if that person is not ready for the meeting. It was necessary to prepare. And John would tell the people who came to him how to prepare. He does not propose anything especially complicated. No lengthy prayers, no special complex purifying rituals.
The main thing is love for one's neighbor and openness to him. And the point is not only that without such openness one's neighbors will inevitably suffer. The point is also that without learning openness in communication with people, it is practically impossible to learn it in communication with God. The skill of openness is much easier to acquire in dealing with a person like yourself than in dealing with God, who is not like you at all. And John recommends this as the best preparation for meeting the coming Messiah. And as an anticipation of the experience of life in the Kingdom, where openness is one of the chief principles.