The Gospel today looks like a game played between the chief priests, the elders and Jesus Christ. "By what authority are you doing these things?"; "Where was John's baptism from?" This dialogue actually reflects something happening among people every so often.
When we reject faith in Jesus Christ we have to face the reality of our life with all its richness but revealed to us from one side only. This actually corrupts our own understanding. We can see the world, deal with problems, find solutions, etc., but no matter how hard we try sooner or later we come to a point where things will pile up. Sometimes it takes just few weeks, other times many years. Either way when this moment comes we have to make a decision and choose between "I will follow my mistakes and reject my limitations" and "I was wrong and I need God to find my true life."
The obstacle in this choice is our need for power and success. The leaders of Israel wanted to know the truth, but because they had power over the people they were afraid to answer Jesus' question and lose everything. Being just one step away from the truth they gave up this chance and preferred to live in the unknown, in the darkness of their own mistake.
Advent asks us a question. "Where is Jesus Christ from?" If He is from God and He is God then we should listen to Him and follow everything he told us. If He is not, then we have to create our own values, rules and ideas but sooner or later we will lose them and evil will take over us.
We do this "quiz" every time we go to confession. The examination of conscience is based on answering the question of where Jesus is from. If He is God then we have to recognize our weaknesses to sin and in this way we can see the truth about ourselves and become free because of His forgiveness. It is one question, but the answer is changing our entire lives.