The Bible is a common-sense book. It was written for the common man. Anyone can read and understand the message it contains. The rules that help us to understand it are, generally, the same rules for any type of communication or writing.
1. Understand the purpose
Jesus “had given commands through the Holy Spirit to the apostles whom he had chosen” (Acts 1:2 ESV). The book of Acts records this statement in its opening and shows how the apostles did indeed obey those commands. (Paul uses the same term for “command” in Acts 13:47 in referring to the mandate “to bring salvation to the farthest corners of the earth.”)
Luke also maps out the geography of that obedience in verse 8: “you will be my witnesses in Jerusalem and in all Judea and Samaria, and to the end of the earth.” Some actually use this verse as the outline for the book. It does indeed show how the disciples carried out the Lord’s order.
Whether stated outright or implicitly, by their emphases and vocabulary, a book or even an entire grouping of books (think, the prophets, for example, or the Pentateuch) will reveal its purpose on reading and examination. One of Luke’s principal interests, for example, is repentance (see Luke 13:1-5; 24:47; Acts 2:38; 5:31; 11:18; 17:30; 20:21; 26:20).
2. Don’t go beyond what is written
Some, like those who believe in a literal, earthly millenium, take Jesus’ answer to the apostles’ question about restoring the kingdom to Israel to mean that he will do so (Acts 1:6-7). After all, he spoke of “times” and “periods,” perhaps “dates.” He did not specifically, at that moment, disabuse them of their idea of an earthly kingdom. But Jesus did not say that God would make the people of Israel an earthly kingdom again. (In fact, he had taught otherwise; see Matt 21:43).
Paul came out and told the Corinthians that they should learn “not to go beyond what is written” (1 Cor 4:6). Stay with the text, don’t go any further than it goes. Don’t speculate, don’t elaborate, don’t fabricate, don’t extrapolate from what is not affirmed nor taught.
Actually, in Acts 1, on restoring the kingdom to Israel, all signs pointed to the contrary. Like completing the number of the apostles to Twelve, before the arrival of the Spirit. Which brings us to no. 3.
3. See the whole picture
Context, both immediate and larger, is a defining factor in communication. All communication takes place within a set of circumstances. Why the rush to find someone to take Judas’s place? Why 12 apostles? There were 12 tribes of Israel. Twelve is the number of the people of God. See Jesus’ statements to the Twelve:
Matthew 19:28: Jesus said to them, Truly, I say to you, in the new world, when the Son of Man will sit on his glorious throne, you who have followed me will also sit on twelve thrones, judging the twelve tribes of Israel.
Luke 22:30: that you may eat and drink at my table in my kingdom and sit on thrones judging the twelve tribes of Israel.
The twelve thrones for the 12 apostles are places of honor. It’s probable that here the phrase, “twelve tribes of Israel,” refers to the church (so Bíblia de Jerusalém; see Mark Black, Luke). Hence, in Revelation twelve also appears: “The wall of the city has twelve foundations, and on them are the twelve names of the twelve apostles of the Lamb” (Rev 21:14).
Luke’s introduction to Acts reminds us that the book makes up part of a greater work that includes the Gospel of Luke. Volume 2, the book of Acts, is still part of the story of Jesus. Some don’t like to read anything into Luke’s affirmation of what Jesus began to do and teach. At the same time, it’s clear that all is done in the name of Jesus (Acts 2:38; 3:12-16).
And it makes up part, albeit the central part, of what used to be called the “scheme of redemption,” or “salvation history.” His description of Jesus’ growth and development, to cite but one example, purposely echoes that of Samuel (Luke 2:40, 52; 1 Samuel 2:21, 26).
Luke is very much aware that he stands squarely within the history of God working to bring salvation to the world.