The thing is, while Christ spoke with authority, as we learn in a later chapter of Mark (Chapter 4) "If any man have ears to hear, let him hear. And He said unto them, “Take heed what ye hear. With what measure ye mete it shall be measured to you; and unto you that hear shall more be given."
We also know from Chapter 29 in Deuteronomy, "Yet the Lord hath not given you a heart to perceive and eyes to see and ears to hear unto this day."
Interestingly in Mark, all heard what Christ had to say in the temple - but they heard it in different ways. The demon driven out recognized Christ's authority and fled in fear. Many of the Pharisees heard and feared for the challenge to their own authority and more importantly - the challenge to their power.
And then those that had ears - and perhaps the heart - to hear, heard the authority in Christ's words and voice, and recognized that God had indeed sent them the Messiah.
In today's world, we are often taught that we should "question authority", and our society does so, sometimes to their own detriment. However, what so many don't recognize in those who walk the talk of the Christian Faith is that we have chosen to submit our will to that of God's, and the authority with which Christ spoke is heard by the ear, and felt in the heart, even today.
Authority is only effective when those who hear the voice of authority choose to submit. And certainly, there are consequences to making other choices - we simply have to decide what authority is worthy of our respect, admiration and love. That choice should be conscious, every single time - but in case you've fallen into a bit of a rut, each time you say the Lord's Prayer, emphasize the word "thy". It's interesting how much more aware we are of our choice - and the actions that should reflect it.
Songs for the Book of Luke lists "The Authority of Christ" as the first song that's quite worth listening to.