Therefore the Book of the Acts of the Apostles begins with it.
The keynote of the 'treatise' lies in the first words, which describe the Gospel as the record of what 'Jesus _began_ to do and teach,' Luke would have gone on to say that this second book of his contained the story of what Jesus went on to do and teach after He was 'taken up,' if he had been strictly accurate, or had carried out his first intention, as shown by the mould of his introductory sentence; but he is swept on into the full stream of his narrative, and we have to infer the contrast between his two volumes from his statement of the contents of his first.
The book, then, is misnamed Acts of the Apostles, both because the greater number of the Apostles do nothing in it, and because, in accordance with the hint of the first verse, Christ Himself is the doer of all, as comes out distinctly in many places where the critical events of the Church's progress and extension are attributed to 'the Lord.' In one aspect, Christ's work on earth was finished on the Cross; in another, that finished work is but the beginning both of His doing and teaching. Therefore we are not to regard His teaching while on earth as the completion of Christian revelation. To set aside the Epistles on the plea that the Gospels contain Christ's own teaching, while the Epistles are only Paul's or John's, is to misconceive the relation between the earthly and the heavenly activity of Jesus.
The statement of the theme of the book is followed by a brief summary of the events between the Resurrection and Ascension. Luke had spoken of these in the end of his Gospel, but given no note of time, and run together the events of the day of the Resurrection and of the following weeks, so that it might appear, as has been actually contended that he meant, that the Ascension took place on the very day of Resurrection. The fact that in this place he gives more detailed statements, and tells how long elapsed between the Resurrection Sunday and the Ascension, might have taught hasty critics that an author need not be ignorant of what he does not mention, and that a detailed account does not contradict a summary one,--truths which do not seem very recondite, but have often been forgotten by very learned commentators.
Three points are signalised as occupying the forty days: commandments were given, Christ's actual living presence was demonstrated (by sight, touch, hearing, etc.), and instructions concerning the kingdom were imparted. The old blessed closeness and continuity of companionship had ceased. Our Lord's appearances were now occasional. He came to the disciples, they knew not whence; He withdrew from them, they knew not whither. Apparently a sacred awe restrained them from seeking to detain Him or to follow Him. Their hearts would be full of strangely mingled feelings, and they were being taught by gentle degrees to do without Him. Not only a divine decorum, but a most gracious tenderness, dictated the alternation of presence and absence during these days.
The instructions then given are again referred to in Luke's Gospel, and are there represented as principally directed to opening their minds 'that they might understand the Scriptures.' The main thing about the kingdom which they had then to learn, was that it was founded on the death of Christ, who had fulfilled all the Old Testament predictions. Much remained untaught, which after years were to bring to clear knowledge; but from the illumination shed during these fruitful days flowed the remarkable vigour and confidence of the Apostolic appeal to the prophets, in the first conflicts of the Church with the rulers. Christ is the King of the kingdom, and His Cross is His throne,--these truths being grasped revolutionised the Apostles' conceptions. They are as needful for us.
From verse 4 onwards the last interview seems to be narrated. Probably it began in the city, and ended on the slopes of Olivet. There was a solemn summoning together of the Eleven, which is twice referred to (vs. 4, 6). What awe of expectancy would rest on the group as they gathered round Him, perhaps half suspecting that it was for the last time! His words would change the suspicion into certainty, for He proceeded to tell them what they were not to do and to do, when left alone. The tone of leave-taking is unmistakable.
The prohibition against leaving Jerusalem implies that they would have done so if left to themselves; and it would have been small wonder if they had been eager to hurry back to quiet Galilee, their home, and to shake from their feet the dust of the city where their Lord had been slain. Truly they would feel like sheep in the midst of wolves when He had gone, and Pharisees and priests and Roman officers ringed them round. No wonder if, like a shepherdless flock, they had broken and scattered! But the theocratic importance of Jerusalem, and the fact that nowhere else could the Apostles secure such an audience for their witness, made their 'beginning at Jerusalem' necessary.