He [Jesus] expresses his authority through his word, the Bible. It is, as John Calvin picturesquely put it, the scepter by which King Jesus rules his people. It is in Scripture that Jesus continues to give us his teaching. When we read it, study it, and seek to obey it, we hear his voice and recognize his authority (John 10:3-5). That is why one mark of the Christian will be loving study of Scripture and a growing obedience to everything Christ teaches us through Scripture.
Sinclair B Ferguson, The Sermon on the Mount: Kingdom Life in a Fallen World.

