Sancti Patris Nostri Epiphanii, Episcopi Constantiae Cypri, ad Physiologum. Eiusdem in die festo Palmarum sermo. (Physiologus)
The first property of the lion is that when he walks in the mountains and scents a hunter, he erases his tracks with his tail, so that the hunter cannot follow him back to his den and capture him. The interpretation of this property is that the lion represents Christ, the spiritual lion, who in becoming incarnate covered his spiritual tracks, that is his divinity, so that those who saw him asked "Who is this king of glory?"
When the lion sleeps, it keeps its eyes open and watches. The lion sleeping with its eyes open represents Christ on the cross; his body sleeps in death, but his divinity keeps watch at the right hand of God. The second property is that the lion cub is born dead, but is brought to life after three days when the father breathes on its face (some accounts say the father roars over the cub). This represents Christ's three days in the grave, after which God his father revived him.
(https://spcoll.library.uvic.ca/Digit/physiologum/animal/lion1.htm, https://spcoll.library.uvic.ca/Digit/physiologum/animal/lion2.htm, ...crazy medieval bestiary! Their observations and forced religious explanations for them are fun to read.)
Bible
Even Absalom's lion-hearted men must fear David's followers
And as soon as some of the people fall at the first attack, whoever hears it will say, ‘There has been a slaughter among the people who follow Absalom.’ Then even the valiant man, whose heart is like the heart of a lion, will utterly melt with fear, for all Israel knows that your father is a mighty man, and that those who are with him are valiant men. (2 Samuel 17:9-10)
Jeremiah prophesied in the hearing of Jerusalem that Israel's own sword devoured their prophets like a ravening lion. (Jeremiah 2:30)
The lion will no longer hurt anything in Zion
"The wolf and the lamb shall graze together; the lion shall eat straw like the ox, and dust shall be the serpent's good. They shall not hurt or destroy in all my holy mountain," says the LORD. (Isaiah 65:25)