Only one is found who is worthy to open the scroll, the Lion of Judah, the Root of David, the Lamb who was slain. This symbolism is not explained, because the Scripture has already explained it (The Throne and the Lamb, pg. 18).
The Lion of the tribe of Judah:
Judah is a lion’s whelp;
From the prey, my son, you have gone up.
He bows down, he lies down as a lion;
And as a lion, who shall rouse him? Gen 49:9.
For it is evident that our Lord arose from Judah, of which tribe Moses spoke nothing concerning priesthood. Heb 7:14.
The Root of David:
There shall come forth a Rod from the stem of Jesse,
And a Branch shall grow out of his roots.
“And in that day there shall be a Root of Jesse,
Who shall stand as a banner to the people;
For the Gentiles shall seek Him,
And His resting place shall be glorious.” Isa 11:1, 10.
And again, Isaiah says:
“There shall be a root of Jesse;
And He who shall rise to reign over the Gentiles,
In Him the Gentiles shall hope.” Rom 15:12.
“I, Jesus, have sent My angel to testify to you these things in the churches. I am the Root and the Offspring of David, the Bright and Morning Star.” Rev 22:16.