Alcuin of York — on Rev 5:5 (COMMENTARY ON REVELATION)

“And one of the ancients said to me: Weep not; behold the lion of the tribe of Juda, the root of David, hath prevailed to open the book, and to loose the seals thereof. By this ancient we understand the order of the prophets, by whose prophecies the Church was comforted, as in The sceptre shall not be taken away from Juda, nor a ruler from his thighs, till he come that is to be sent. [Gen. 49:10] Note also that Christ is here called a lion because he overcame the Devil, while in the following verse he is called a lamb because he redeemed the world by sacrificing himself. As for the root of David, it means the kin and son of David. Moreover it should be noted that in the words hath prevailed, he used the past for the future, as in They have dug my hands, etc. [Ps. 21:17]”