Luke 6:17

And stood in the plain - It is not affirmed, however, that he stood in the plain when he delivered the following discourse. There has been some doubt whether the following discourse is the same as that recorded in Matthew 5; Matthew 6; Matthew 7, or whether the Saviour “repeated” the substance of that discourse, and that Luke recorded it as he repeated it. The reasons which have led many to suppose that they refer to the same are:

1. That the beginning and the close are alike.
2. That the “substance” of each is the same. And,
3. That “after” the discourse was delivered, both affirm that Jesus went to Capernaum and healed the servant of the centurion, Matthew 8:5; Luke 7:1.

On the other hand, “Matthew” says that the sermon was delivered on the “mountain” Matthew 5:1; it is thought to be implied that “Luke” affirms that it was in the “plain.” Matthew says that he “sat;” Luke, that he “stood.” Yet there is no reason to suppose that there is a difference in the evangelists. Jesus spent the night on the mountain in prayer. In the morning he descended into the open plain and healed many. While there, as Luke says, he “stood” and received those who came to him, and healed their diseases. There is no impropriety in supposing that, being pressed by multitudes, he retired into the mountain again, or to an eminence in the plain, or to the side of the mountain, where the people might be more conveniently arranged and seated to hear him. There he “sat,” as recorded by Matthew, and delivered the discourse; for it is to be observed that Luke does “not” say that he delivered the sermon “on the plain,” but only that he “healed the sick there.”

Tyre and Sidon - See the notes at Matthew 11:21.