One of the most paradoxical parts of Revelation is John's vision of the lion followed immediately by a slain lamb. As the vision opens in Revelation 5:1-5, John is told that the Lion of the tribe of Judah has prevailed to open the scroll sealed with seven seals. But as John looks for a lion, he sees a lamb instead (verse 6). It is a grisly sight, for the lamb appears to have been slaughtered. This is the first occurrence of lamb imagery in Revelation. It's as though the image has been kept for its dramatic entrance precisely until this point.
The Lamb is Revelation's defining title for Christ. This lamb imagery is connected to the Old Testament book of Isaiah. The imagery is central to the prophecy of the suffering servant in Isaiah 53. There the future sacrifice for sin is pictured as a lamb being led to the slaughter. Jesus fulfilled this prophecy. He was the Lamb of God sacrificed for the sins of the world.
In the book of Revelation, this lamb metaphor has a double image. It tells us the slaughtered Lamb is coming a second time as the Word of God's wrath to require the blood of all who oppose him (Revelation 6:16; 19:7, 9, 11-16). But Jesus Christ, the Lamb, first shed his own blood. That is what makes him worthy to open the scroll and reveal the message of the book of Revelation. The angelic hosts of heaven praise the Lamb, saying he is worthy to open the book's meaning because he was killed. With his blood he has "purchased people for God from every tribe and language and people and nation" (Revelation 5:9).
Thus, there is a paradox about the picture in Revelation 5. Though its central figure has triumphed (the Lion), he appears to have been conquered and killed (the Lamb). Jesus overcame the world by sacrificing himself. His supreme act of triumph was accomplished by shedding his own blood (Revelation 1;5; 5:9; 7:14; 12:11).
Jesus' death as the Lamb of God gained a victory over the cosmic powers in opposition to God. The Lamb of God defeated Satan, sin and the power of the grave. That is the message of Revelation 5: Jesus has won the victory over his enemies by sacrificing his life as the Lamb. Through this act he is worthy to return as the "Lion" to rule the nations.
Thus, Jesus as Lamb tells Christians — his lambs — that they are to suffer the outrageous darts of their oppression in patience. They must be submissive to God and place their unswerving allegiance with him. He will vindicate the cause of those whose faith remains in him.