"They returned once more to Jerusalem. As he was walking in the temple area, the chief priests, the scribes, and the elders approached him and said to him, "By what authority are you doing these things? Or who gave you this authority to do them?"
Jesus said to them, "I shall ask you one question. Answer me, and I will tell you by what authority I do these things. Was John's baptism of heavenly or of human origin? Answer me." They discussed this among themselves and said, "If we say, 'Of heavenly origin,' he will say, '(Then) why did you not believe him?' But shall we say, 'Of human origin'?"--they feared the crowd, for they all thought John really was a prophet.
So they said to Jesus in reply, "We do not know." Then Jesus said to them, "Neither shall I tell you by what authority I do these things."
We'll never know what was going on in our Lord's brain, this side of heaven. But then the nature of authority itself is problematic, especially in a religous community such as the Church.
There are some things, however, which can be said specifically about how authority works in the Church.
The Church's authority is derivative. The reason the Church can speak authoritatively is not because of something she possesses in herself. Rather, the church's authority began and stems from her Lord, from the Incarnation of God in human flesh.
Whatever the Church speaks definitively arises directly from her beginnings: "You are the Christ, Son of the Living God" and "Jesus is Lord" are statements which carry a weight beyond their words. That weight requires the Church to speak authoritatively but also to acknowledge that the Deposit of Faith remains a gift. "Flesh and blood did not reveal this to you, but my Father who is in heaven."
The Church's authority is hedged about by a history of faith and a thoughtful reference to reason. Dogmas aren't true because the Church says they are true. Truth comes from listening attentively to those who have gone before us in faith and also using the rational powers God has given to apply those truths to our own time. The real derailing takes place when teachers, theologians, and believers at all levels and intensities turn too far to one side or the other. It's a real balancing act to walk with the Fathers and Mothers who teach us but also give due weight to our own historical circumstance.
The Church's authority exists solely for the well-being of others. In the final analysis the Church's authority really exists in service to the salvation of souls. This is not a utilitarian argument. This is a pragmatic truth of which we all need to be reminded each and every day.
Don't believe me? Go to the source.... the Johannine letters. Here we find the emblematic phrase of our current Holy Father, "God is Love" and its immediate and necessary corollary, "Let us love one aother."
Throughout the rest of 1 John and even in the brief notes comprising 2 and 3 John one can experience the death throes of the Apostolic era... and the birth of Churchly authority. Those who followed the Beloved Disciple are beginning to think intently about what life will be like after he passes from the scene. It isn't pretty and it isn't easy. But it had to happen.
Benedict XVI has written helpfully about this authority in the first section of his new book, Jesus of Nazareth. He is discussing the third of Jesus' temptations, the one on the mountain, and Benedict flashes forward to the mount of Ascension to discourse on authority (pp.38-39):
"The risen Lord gathers his followers "on the mountain" (cf Mt 28:16). And on this mountain he does indeed say "all authority in heaven and on earth has been been given to me" (Mt 28:18). Two details here are new and different. The Lord has power in heaven and on earth. And only someone who has this fullness of authority has the real, saving power. Without heaven, earthly power is always ambiguous and fragile. Only when power submits to the measure and the judgment of heaven- of God, in other words- can it become power for good. And only when power stands under God's blessing can it be trusted."