Revelation 5:5

one of the elders It is idle to speculate which; even if it be assumed certain that the twenty-four are the Patriarchs and Apostles, they represent their federal office, not their individual character. We can hardly suppose that St John saw himselfseated among them.

the Lion of the tribe of Juda Genesis 49:9.

the root of David Revelation 22:16; Isaiah 11:1; Isaiah 11:10, where however we have the Root of Jesse. Some distinguish the two phrases, that Christ is said to grow from the obscure Jesse in reference to the time of His humiliation, from the kingly David in reference to His exaltation.

hath prevailed to open Lit. hath conquered: Christ's victory (see Revelation 3:21 and ref.) has this consequence, that He can open. There is a well-supported reading, "the Lion hath conquered, Who openeth" … but this is grammatically easier, and less effective both presumptions in favour of the text.

to loose Should be omitted as a gloss: we hear of "opening the seals" all through the next chapter.