ISB ~ Matthew 5 v1

on the mountain:The setting recalls the giving 5 of the Law on Mt. Sinai (Ex 19-24). However, Moses brought the Law down the mountain to the people, whereas Jesus delivers his teaching to disciples who have come up the mountain.

• The mountain signifies the higher precepts of righteousness, for the precepts given to Israel were lower. God gave lesser laws to those requiring the bonds of fear, but higher laws to those ready to be set free by love. The higher precepts are for the kingdom of heaven, just as the lower precepts were for a kingdom on earth (St. Augustine, On the Sermon on the Mount 1, 1, 2).

he sat down:The posture of a Jewish rabbi speaking with authority (cf. 23:1-2; Jn 8:2).