The possession of the covenant book, and the ability to open and read it demonstrated the king’s right to rule.
The history of the Old Testament shows that only rarely did Israel’s kings follow the covenant book.
Whenever the king did not follow the instructions of the covenant book, the prophets would declare this book of the law would be sealed. Isaiah 29:9-14 links to not being able to read the scroll, caused by it being sealed through disobedience. Symbolically, this describes the inability of humans to discern and understand the revealed will of God.
When Jesus was on earth, Israel no longer had a king on the throne—from the line of David—leading the people in harmony with the covenant. Many people longed for the promised one to come and give them the leadership they needed. The New Testament recognises this was fulfilled in Jesus. (see Luke 1:32, 33; 4:18, 19; Acts 2:26).
In Revelation 5, the sealed scroll symbolises God’s promise to give the kingdom to His people. It is handed to Christ, demonstrating that His sacrificial death and resurrection brought the promise to fulfilment. In receiving the scroll, Christ was given Lordship: the authority and power to reign.