And the cow and the bear shall feed; their young ones shall lie down together: and the lion shall eat straw like the ox.
Read Chapter 11
Ambrose of Milan
The gift of water is so great that it causes both oxen and lions to feed, in correspondence with that prophetic saying about the holiness of the church: “Then the wolf and the lamb will feed together, and the lion will eat straw with the ox.” Nor is it any marvel that water operates the same way in the church, such that thieves whose sins were washed away may be compared with the innocent. - "Six Days of Creation 5.2.6"
It is also added here: “and a small child will lead them.” Who is this small child, if not the one about whom it was written: “A child is born to us, a son is given to us”? - "Homilies on Ezekiel 2.4.3"
For when Isaiah observed the life of sinners devoured by the ancient and insatiable enemy, he said, “The lion shall eat straw like the ox.” But what is signified by the words hay and straw except the life of the carnal? Of which it is said by the prophet, “All flesh is hay.” He then who here is “Behemoth,” is there a “lion”; they who are here called “hay,” are there called “straw.” But the mind strives to enquire why this lion in Isaiah, or Behemoth as he is called by the voice of the Lord, is in both passages compared not with a horse but an ox. But we ascertain this the sooner, if we consider what is the difference of foods in the two animals. For horses eat hay, however dirty, but drink clean water only. But oxen drink water, however filthy, but feed only on clean hay. What then is it, for which this Behemoth is compared with an ox, which feeds on clean food, except that which is said of this ancient enemy by another prophet; “His food is choice.” - "Morals on the Book of Job 6.32.1...
Where and when, therefore, will this blessing be accomplished except in the kingdom of God, where grain, wine and oil are in abundance? The earth will yield its fruit generously and every evil will be destroyed, as Isaiah said: “In those days, the lion will eat straw with the ox, the wolf and the lamb will feed together, and a small child will put his hand in the den of an asp without being harmed.” In his kingdom, God will recreate the world as wonderfully as it was made at the beginning, before the first man sinned. For after he violated the word of God, all things were corrupted, profaned and cursed when God said, “Cursed is the ground because of your works.” The passing form of this world, therefore, will become the kingdom of the saints and the liberation of creation. - "Origen’s Tractate on the Books of Holy Scripture 5.36–37"