The audience and the setting for today's gospel episode are the same: the chief priests and elders of the people who have confronted Jesus in the temple. They considered themselves to be the elite among the Jews (along with the Sadducees). The kind of change of life that John the Baptist was preaching did not apply to them, much less his message about the Messiah! Those who were considered by them to be the worst kind of sinners were the ones who heard John's message and followed Jesus. Their lives mirrored the life of the first son in the parable. The chief priests and elders of the people thought they had said, "Yes sir!" but their stubborn resistance to Jesus' message showed that they had not "followed orders!" They saw no reason to change. They were of "the better sort."
Young parents know well the changes that must occur in their life together when their first child (any subsequent ones) is born. That child is a message of new life that requires "new life" of the parents. They cannot simply sit and admire the baby. They have to take care of him/her! The task only begins at conception and birth. A whole lifestyle, called parenthood, is their challenge.
The liturgical celebration of Advent/Christmas means more than saying, "Yes sir!" and then putting away all the decorations till next year. We may feel that nothing more than the usual celebration is necessary with no personal change or conversion implied. But the baby in the manger is summoning us to do more than simply admire and adore and go back to "business as usual!" A change of mind, heart and behavior is expected! The tax collectors and prostitutes realized this. The chief priests and elders did not. With which group will we identify ourselves when we set up the nativity scene? AMEN