Verse 5: And one of the elders saith unto me, Weep not: behold, (Gen. 49:9, 10; Heb. 7:14) the Lion of the tribe of Juda, (Is. 11:1, 10; Rom. 15:12; Rev. 22:16) the Root of David, hath prevailed to open the book, (Rev. 5:1; 6:1) and to loose the seven seals thereof.
[And one, etc.] Who bears the person of the entire order (Cotterius). One of the chiefs of the Church, not triumphant, but militant. For theirs it is to teach the Church (Cluverus). See how great is the honor of Presbyters. The Angel teaches Daniel, who desires to know future things; a Presbyter teaches John. The sense is: It was going to be revealed by God to a certain one of the Jerusalem Presbyters that Christ was going to make known to the Jerusalem Church all things that pertain unto her through John (Grotius).
[Weep not] Be not thus grieved: thou shalt have what thou wishest (Grotius).
[Behold, he overcame] That is, He prevailed (Ribera, Menochius), obtained (Menochius, Grotius, Piscator), from the Father, by His own merits (Piscator), that which thou didst reckon hopeless (Grotius).
[The Lion (whose it is properly to overcome [Cotterius]: Now, there is ἔμφασις/emphasis here: He who appears as a Lamb is actually a Lion [Grotius]) of the tribe of Juda] That is, Christ, who was of the tribe of Judah (Menochius, Drusius, Grotius), as His Genealogies teach, and Hebrews 7:13, 14 (Grotius), which tribe is compared to a lion (Menochius), and the ensign of which was the Lion (Drusius). There is an allusion to Genesis 49:9 (Ribera, thus Cotterius, Piscator, Grotius, Forbes, Durham). Which shows that the prophecy was fulfilled in Christ in a more sublime sense. To which is also able to be added that in Numbers 24:17. And because of those words of Jacob the Lion was always on the banner of Judah (Grotius).
[The Root of David] It is taken from Isaiah 11:10 (Cluverus, thus Durham, Mede, Grotius). Ἡ ῥίζα, the root, that is, ὁ ἐκ τῆς ῥίζης, the One from the root (Mede’s Works 1112): a shoot out of the root of David (Grotius, thus Gomar, Cluverus), out of the stock or family of David (Menochius, Drusius), whence it is everywhere predicted that He was going to rise, as in Psalm 72; 89; 132; Isaiah 9:7; Jeremiah 23:5; etc.: that is to say, descended according to the promises from David (Piscator, thus Forbes), and from Judah, with Moses and the Prophets testifying (Forbes). Root, that is, He, whom that root of David put forth (Beza). A metonymy (Grotius, Gomar), which sort is in Hosea 14:5, 6 and Isaiah 11:10, which passage is applied to Christ in Romans 15:12. Add Isaiah 53:2; 1 Maccabees 1:10. Now, this title agrees with Christ in an extraordinary manner, in whom all the old Prophecies of good things are fulfilled in a much more excellent sense. Formerly temporal things were announced, the eternal things lying hidden (Grotius). Others: He is called the Root because that tree was broken and lopped off even unto the root (Cluverus). In Revelation 22:16 He is called both the root and the offspring of David (Pareus, Durham), as He is called the Lord and the son of David in Matthew 22:45: offspring, as He is man; root, as He is θεάνθρωπος/God-man, the Mediator, and the Head of the Church (Durham); as He is David’s creator (Ribera), support, fountain and author of life (certain interpreters in Cluverus), of sanctification, of exaltation, of all the good things that David had: or, the word David is able to be taken adjectivally, that is to say, the Davidic Root, understand of the Nations, or of the Church, or of the elect (Pererius). He is said to be of David, so that it might be indicated that Christ is man; and the root of David, so that it might be signified that He is greater than all men, even the Lord of David and all the Fathers (Cocceius).
[To open, etc.] There is a σύλληψις/syllepsis here. For ἀνοῖξαι, to open, is properly spoken of the pages; λῦσαι, to loose, of the seals, as in verse 2. The sense: ἀνοῖξαι τὸ βιβλίον λύσας τὰς σφραγῖδας, to open the book having loosed the seals. Daniel, a figure of Christ, reads what others prevailed not to read, Daniel 5:8 and following (Grotius).
And one of the elders saith unto me, etc.: We must remember that John is here describing a vision, and that part of it which is but introductive to the material parts of it. He had in his vision seen a book in the right hand of God the Father, sitting upon his throne of glory; he had heard an angel proclaiming, If any were worthy, he should open the book, and loose the seals. None appeared to answer that voice; he was troubled; he thought he heard one saying to him, Be not troubled, the book shall be opened. Christ shall open the book, and loose the seals of it, who is here expressed under a double character: 1. The Lion of the tribe of Judah; he is so called, undoubtedly, with allusion to Jacob’s prophecy, Genesis 49:9, 10, wherein Judah was compared to a lion’s whelp, because he should be victorious. Christ was to be born of this tribe, and was to be a great Conqueror. 2. He is called the Root of David; he was a Branch of David, as he was man, but the Root of David, as he was God; therefore David, Psalm 110:1, called him Lord, though he was his Son. Hath prevailed with his Father to open the book, and to loose the seven seals thereof; for leave to open the book, and loose the seals thereof; that is, to reveal those things that are the counsels and purposes of God relating to his church, and the affairs thereof, to the world’s end. I do not think we are at all concerned to inquire who is here meant by one of the twenty-four elders. As in parables there are some things put in merely to complete the feigned history, so in the relation of visions some things of that nature are put in, which need not a particular explication. The sum is, That while John was troubled for fear he should not know what was in the book, he was told by one of those who attended the throne, that he need not be troubled, for Christ had obtained a liberty from his Father (in whose power only times and seasons for future things were) to reveal these counsels of God as to things to come.
 Greek: καὶ εἷς ἐκ τῶν πρεσβυτέρων λέγει μοι, Μὴ κλαῖε· ἰδού, ἐνίκησεν ὁ λέων ὁ ὢν ἐκ τῆς φυλῆς Ἰούδα, ἡ ῥίζα Δαβίδ, ἀνοῖξαι τὸ βιβλίον καὶ λῦσαι τὰς ἑπτὰ σφραγῖδας αὐτοῦ.  See Daniel 7:16; 8:15, 16; 9:21, 22.  See Matthew 1; Luke 3.  1 Maccabees 1:10: “And there came out of them a wicked root, Antiochus surnamed Epiphanes, son of Antiochus the king, who had been an hostage at Rome, and he reigned in the hundred and thirty and seventh year of the kingdom of the Greeks.”  In Codex Alexandrinus and in the great majority of Byzantine manuscripts, the word λῦσαι, to loose, is wanting. Consequently, there is a syllepsis here, ἀνοῖξαι, to open, taking both the book and the seals as objects, but properly applying only to the book.