Acts is Luke’s second account – compare Acts 1 verse 1-3 with Luke 1 verse 1-4. Luke 24 closes with Jesus’ ascension compare that to account the Acts 1 account which commences with the same event. Luke’s first record closes with Jesus praying as he is taken to heaven as does Acts 1. For 40 days Jesus spoke with his disciples of the kingdom of God on earth, as the reconstituted kingdom of Israel. The only question the Apostles had was “Is the time for the kingdom now?” The time, as verse 7 indicates, is known only by Jesus’ Father. By AD 96 when the book of Revelation is written Jesus then knew this time. But based on Jesus’ commission for them to preach to the entire world it would obviously be some time distant. And following the words of the angels in recorded in verses 9-11 that kingdom would not come until our Lord’s return to earth. From verses 12 to 26 a replacement is appointed for Judas, whose behaviour was the subject of prophecy – Psalm 109 verse 8 (in fact it is instructive to read the entire Psalm as it will provide us with an insight as to what motivated Judas). That successor is named as Matthias.