Jesus' title as the Son of Man, He has title to the Earth and the World.
Jesus' title as the Son of Abraham, He has title to the Land of Palestine, and all included in the land God gave Abraham.
Jesus' title as the Son of David, He has title of the Throne of David.
In the Gospels Jesus is given four titles:

            the Son of David,
            the Son of Abraham,
            the Son of Man,
            the Son of God.
Satan is not evicted from the earth at once.

          He contests the claim by the Lamb and it is only after a prolonged conflict that he is finally dispossessed and cast into the Lake of Fire.
When the Lamb leaves the Throne to take the Book, His work as a Mediator stops, and His Redemptive work begins.

          When our Kinsman Redeemer is handed the Book, the Deed to the Purchased Possession, He has the right to break its Seals, and claim the Inheritance, and dispossess the former owner, Satan.
The Seven-Horned Lamb.

       This is the time when the man Christ Jesus, who gave Himself as a Ransom [on the Cross] for the redemption of the lost inheritance, will be testified to before the Throne of God, by the redeemed; man, angels, and every creature in Heaven and Earth, and under the Earth. 
1 Timothy 2:5-6;   Revelation 5:8-14.
That the Lamb was not an animal is clear from verse seven, where it says, "And He [the Lamb] came and took the Book out of the right hand of Him that sat upon the Throne."

       This is the most reverant individual act recorded in the Word.

        The Redemption of all creation depended upon it.

          It is still in the future and takes place after the Church has been "caught out and judged, before the Tribulation Period begins.
John looked for a Lion and saw a Lamb.

         But the Elder was right in calling it a Lion, because Jesus was about to take His Title as the Lion of the Tribe of Judah, and reign and rule with Kingly power.
John saw what he had not noticed before, a Lamb, as it had been slain, standing in the midst of the Throne, and of the "Four Living Creatures."

         John had not seen the Lamb before, because He had been seated on the Throne with the Father, and came from out of the Glory of the Throne as the Elder spoke.
John wept because He knew what the Book was, and that if there was no one to open that Book of Redemption, all hope of the redemptions of the earth and of man was gone.

        John's sorrow was short, for one of the Elders said, "Weep not: behold, the Lion of the Tribe of Judah, the Root of David, hath prevailed to open the Book, and to loose the Seven Seals thereof."
John said, there was no man (redeemed man) in Heaven or in Earth, neither under the Earth, who was able to open the Book, neither to look thereon.

        It wasn't a question of the worthinesss of some angelic being, such as Michael or Gabriel, to open the Book, but of a Man.

               When John saw that there was no one worthy to open the Book he wept.
When the 'strong angel' proclaimed with a loud voice, "who is worthy to open the Book, and to loose the Seals thereof?" that was the call for the "KINSMAN REDEEMER" to appear.
Happy is he that trusts in the Lord
The Old Testament story of Boaz and Ruth in Ruth 4:1-12, illustrates the ways and purposes of a kinsman.

        The kinsman who redeemed the property was call the Redeemer.
When the time comes for the Redemption of the purchased possession Jesus will claim it.

         That time and the act is described in the Bible we are now considering.

                   The Seven Sealed Book, is the Deed to the redeemed inheritance.
To become a kinsman Jesus had to be born into the human race, by the virgin birth.

                  Jesus paid the price on the Cross
1 Peter 1:18-20, but He has not claimed what He purchased.
Redemption means the legal repossession of all that Adam lost.

      Adam was powerless to redeem the lost possession, but the law provides [Leviticus 25:23-24] that a kinsman may redeem a lost possession.

            That Kinsman has been provided by
                                Jesus Christ.
When Adam sinned he lost his inheritance of the earth and it was given to Satan, to the disinheritance of all of Adam's seed.

         The forfeited title of the earth is in God's hands and is waiting redemption, which means the legal repossession of all that Adam lost in the Fall.