Why do Christians like the Lion?
The Lion of Judah is a phrase in the Book of Revelation that represents JESUS.
Jesus came from the tribe of Judah.
[Revelation 5:5King James Version (KJV)
5 And one of the elders saith unto me, 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.] Jesus can open the book.