The assigned gospel lesson features the 9 Beatitudes from the Sermon on the Mount. The Sermon on the Mount begins in Matthew 5:1 when Jesus sat down on the mountain and called his disciples to himself. In those days, teachers often sat to do their teaching. It was a position of authority. Even today, when the Pope has an especially authoritative teaching, he speaks “Ex Cathedra,” which means “from the chair.” (*See Note)  The Power of Humility and Meekness

The Sermon on the Mount ends in Matthew 7:28-29 where we read: 

And when Jesus finished these sayings, the crowds were astonished at his teaching, for he taught them as one who had authority, and not as their scribes. 

For example: When Jesus said, “Blessed are the poor in Spirit for theirs is the kingdom of heaven,” he may have been summing up a much longer discourse in which he described exactly what it meant to be “poor in Spirit.”

Now it took me about seven minutes to read aloud the three chapters in Matthew that make-up the Sermon on the Mount.  This does not mean that Jesus used just seven minutes in giving the sermon.  The late Dr. Bruce Metzger, who taught New Testament at Princeton Theological Seminary, told his students that most of the short, punchy statements in the sermon are summary statements which Jesus gave to his disciples to help them remember a much longer, more detailed block of teaching.