Acts 1:4

And being assembled together with them
At their last meeting at Bethany, or Mount Olivet, which was by appointment: some render the words, as the Vulgate Latin, "and eating with them"; which was one of the proofs he gave of his being alive; and so the Syriac version renders it, "and when he had ate bread with them", and the Ethiopic version, "and dining with them", which he might do more than once; see ( John 21:12 John 21:15 ) this was the last time, when he

commanded them that they should not depart from Jerusalem;
which does not necessarily infer, that they were then at Jerusalem; for they might be, and they seem rather to be at Bethany, or on the Mount of Olives, from whence they afterwards returned to Jerusalem; and from thence they had orders not to depart, where the blood of Christ had been shed, and where were his greatest enemies, and where the disciples might have no inclination to have gone, and much less to abide, but so it must be, partly for the glorifying of Christ by the effusion of his Spirit on the apostles in the place where he had suffered the most reproach; and partly because the Gospel, the word of the Lord, was to go out of this place, according to the prophecy in ( Isaiah 2:3 ) as also because a Gospel church was to be fixed there, and a very large number of souls to be converted, and added to it: wherefore they were bid to go thither, and not stir from thence,

but wait for the promise of the Father;
that is, the pouring forth of the Spirit, which God the Father of Christ; and of his people, had promised should be in the last days, ( Joel 2:28 ) and which Christ had promised his disciples from the Father, ( John 14:16 ) ( 15:26 ) ( 16:7 ) .

which, saith he, ye have heard of me;
or "by", or "out of my mouth", as the Vulgate Latin and Ethiopic versions, and Beza's most ancient copy read; referring to the above passages, or to what follows: and which he the rather mentions, to assure them of its accomplishment, since it was both a promise of the Father, all whose promises are yea and amen; and he had also told them of it, neither of whose words could possibly fall to the ground.