What does Acts 8:31 mean?
Philip is one of the first deacons of the church (Acts 6:5) and the first significant Christian missionary to Samaria (Acts 8:5–25). An angel has directed him to a road that leads down from Jerusalem to Gaza on the coast of the Mediterranean Sea. While there, he notices an Ethiopian court official reading aloud a passage from the book of Isaiah that talks about the Suffering Servant.The Ethiopian court has known about the Jewish God since at least the time of Solomon, when the Queen of Sheba came to give homage to the wisest man in the world (1 Kings 10:1–13). Years later, an Ethiopian eunuch who served the king of Judah rescued the much-abused prophet Jeremiah from a cistern (Jeremiah 38:7–13). This man comes from a culture that has known the Jewish God for a long time, but he doesn't understand all the Messianic prophecies, so he asks Philip for help.
He's not alone. Today, Jews almost always skip over Isaiah 53. They can't accept that their triumphant Messiah could be the same person as the Suffering Servant. They and the Ethiopian provide an important lesson for modern-day Jesus-followers.
The Protestant Reformation occurred in part because the Roman Catholic Church considered the edicts of the pope and the traditions of the church to have the same authority as the Scriptures. Sola Scriptura is the conviction that only the Bible is God's infallible message, and so it is the fundamental source and judge of all doctrinal questions. It is true that the Bible has an authority that human teachers can never share. Unfortunately, some believers today have taken this to mean it is inappropriate to use any extra-biblical help to interpret Scripture—including other people.
It is true that Jesus sent the Holy Spirit to guide us and explain what we should know (John 16:13), but the Spirit also gifts teachers and preachers to explain the Scriptures (Romans 12:4–8). If those teachers write down their insight instead of only speaking from behind a pulpit, they are writing a commentary—BibleRef.com is a commentary. If a passage is difficult there's nothing wrong with asking for help, as the Ethiopian official does. In fact, Jesus' phrasing of the Great Commission, like the comment made here, makes it clear that no one is meant to interpret or learn about Scripture entirely alone (Matthew 28:19–20).