The Sure Foundation
Exegetical Notes by Brian Stoffregen at CrossMarks Christian Resources makes the following observations about this passage:
"What amazed the crowds was the authority with which Jesus taught. (Not necessarily what he said.) The contrast is presented between Jesus' authority and the authority of their scribes.
Where did scribes derive their authority? From their knowledge and training in scriptures!
This suggests to me that knowing all the right stuff (even the stuff from the Bible) still isn't quite the way through the narrow gate or hard road or into the kingdom of heaven; but being in a relationship with God. Being grounded on the firm foundation of God's power and revelation in Jesus.
One could be a wiz at Bible trivia and still not totally trust God for his salvation. In fact, a wiz at the Bible may have more troubles totally trusting God, because it would be easy to trust his/her knowledge about the Word. Those who, like the Pharisees, are superb at obeying the law, may trust their obedience rather than the power of God. Those who know Jesus as Lord and do mighty miracles in his name, may trust their own abilities rather than God.
There are two ways presented in the conclusion of the Sermon on the Mount. One way is based on looking at what I do -- especially looking at the good, obedient, religious stuff. The other way is based on trusting what God is doing; seeking to know and love us, filling us with Spiritual sap, so that we are good people, who bear good fruit motivated by something deep inside of our being, being our rock foundation that keeps us secure in the midst of the storms of life."