Ver. 13-15. We have this piece of history, or rather something to which it relates, both in Matthew and in Luke, only Mark hath this peculiar to himself, that our Saviour did this upon a mountain. It is the opinion of Bucer, that this was the mountain at the foot of which he preached the sermon largely recorded, Matthew 5:1-7:29, and (as some judge) more shortly by Luke 6:17-45: he thinketh the multitude here mentioned is the same with that mentioned Matthew 4:25, and Luke 3:7, and that our Saviour did not go up into this mountain to preach, or ordain his disciples, but only to pray, and to discourse with some of his disciples more privately about spiritual mysteries. That it was at this time that he continued all night in prayer to God, Luke 6:12; and in the morning called unto him such of his disciples as he thought fit, and discoursed with them his intentions concerning them, telling them,
1. That he had chosen them to be with him, ordinarily, to be eye and ear witnesses of what he spake and did.
2. That he designed soon after to send them out to preach; which we read he did, Mark 6:7 Matthew 10:1; to give them a power to heal sicknesses, and to cast out devils: so that this chapter only mentions Christ's election of them, not his actual sending them, which is discoursed Mark 6:7-13, as also Matthew 10:1-42. These things being privately transacted on the mountain, Bucer thinks he came down into the plain at the foot of the mountain, according to Luke 6:17, and there preached that sermon mentioned Matthew 5:1-7:29, as we before said. The evangelist telling us that he called to him which of his disciples he would, lets us know, that he chose them, and not they him; that the choice of them was of his free grace and mercy; and his continuing all night in prayer before this choice, lets us know the gravity of the work of choosing persons fit to be sent out to preach the gospel.