"The lion is the mightiest of the beasts; he will quail at the approach of none [...] The name lion, leo, of Greek origin, is altered in Latin. For in Greek it is leon; it is not a genuine word, because it is in part corrupted. For the Greek word for lion is translated 'king' in Latin, because the lion is the king of all the beasts. There are said to be three kinds. Of these, the ones which are short in stature, with curly manes, are peaceable; the tall ones, with straight hair, are fierce. Their brow and tail show their mettle; their courage is in their breast, their resolution in their head. They fear the rumbling sound of wheels, but are even more frightened by fire. The lion takes pride in the strength of its nature; it does not know how to join in the ferocity of other kinds of wild beasts, but like a king disdains the company of large numbers. Of the three main characteristics of the lion. Those who study nature say that the lion has three main characteristics. The first is that it loves to roam amid mountain peaks. If it happens that the lion is pursued by hunters, it picks up their scent and obliterates the traces behind it with its tail. As a result, they cannot track it. Thus our Saviour, a spiritual lion, of the tribe of Judah, the root of Jesse, the son of David, concealed the traces of his love in heaven until, sent by his father, he descended into the womb of the Virgin Mary and redeemed mankind, which was lost". 

(https://www.abdn.ac.uk/bestiary/ms24/f7r)

Not knowing of his divine nature, the Devil, the enemy of mankind, dared to tempt him like an ordinary man. Even the angels on high did not know of his divinity and said to those who were with him when he ascended to his father: 'Who is this king of glory?' The second characteristic of the lion is that when it sleeps, it seems to have its eyes open. Thus our Lord, falling asleep in death, physically, on the cross, was buried, yet his divine nature remained awake; as it says in the Song of Songs: 'I sleep but my heart waketh' (5:2); and in the psalm: 'Behold, he that keepeth Israel shall neither slumber nor sleep' (121: 4). The third characteristic of the lion is that when a lioness gives birth to her cubs, she produces them dead and watches over them for three days, until their father comes on the third day and breathes into their faces and restores them to life. Thus the Almighty Father awakened our Lord Jesus Christ from the dead on the third day; as Jacob says: 'He will fall asleep as a lion, and as a lion's whelp he will be revived' (see Genesis, 49:9). Where men are concerned, it is the nature of lions not to grow angry unless they are harmed. An example which thoughtful men should heed; for men grow angry even when they have not been harmed, and they oppress the innocent, although Christian law bids them set even the guilty free. The compassion of lions is apparent from endless examples. They spare those whom they have brought down. They allow captives whom they encounter to return home. They vent their rage on men rather than women. They do not kill children except in time of great hunger. Equally, lions refrain from over-feeding. First, because they drink and feed on alternate days; and often, if their food remains undigested, they postpone the Next feed. Then, because they feel uncomfortable when they have devoured more meat than they should, they insert their paws in their mouth and pull the food out, of their own accord. And when they have to take flight, they do exactly the same thing if they are full. Missing teeth show that a lion is old. Lions mate face to face; and not only lions, but lynxes, and camels, and elephants, and rhinoceroses, and tigers. [Lionesses, when] they first give birth, bear five cubs.

(https://www.abdn.ac.uk/bestiary/ms24/f7v)

In the years which follow, they reduce the number by one at a time. Afterwards, when they are down to one cub, the fertility of the mother is diminished; they become sterile for ever. The lion disdains to eat the Previous day's meat and turns away from the remains of its own meal. Which beast dares to rouse the lion, whose voice, by its nature, inspires such terror, that many living things which could evade its attack by their speed, grow faint at the sound of its roar as if dazed and overcome by force. A sick lion seeks out an ape to devour it, in order to be cured. The lion fears the cock, especially the white one. King of the beasts, it is tormented by the tiny sting of the scorpion and is killed by the venom of the snake. We learn of small beasts called leontophones, lion-killers. When captured, they are burnt; meat contaminated by a sprinkling of their ashes and thrown down at crossroads kills lions, even if they eat only a small an amount. For this reason, lions pursue leontophones with an instinctive hatred and, when they have the opportunity, they refrain from biting them but kill them by rending them to pieces under their paws.

(https://www.abdn.ac.uk/bestiary/ms24/f8r)