Biblion (βιβλίον) refers to a written document — a book, scroll, certificate, or written record. It appears throughout the New Testament for the scroll of the Law (Luke 4:17–20), a certificate of divorce (Matthew 19:7), books of magic (Acts 19:19), and most significantly the sealed book of Revelation (5:1–9). In Revelation, the "biblion" opened by the Lamb becomes the central object of heavenly drama.
The sealed biblion of Revelation 5 is the scroll containing God's redemptive plan for all history — sealed with seven seals, requiring one "worthy" to open it. No one in heaven, earth, or under the earth could open it until the Lamb who was slain (5:9) took it. This is one of Scripture's most exalted Christological moments: all of history's meaning is contained in a book that only Jesus Christ has the authority and worthiness to unseal. "He is worthy!" — the anthem of heaven. Creation's entire story belongs to the Lamb.