Then the wolf shall be a guest of the lamb, and the leopard shall lie down with the kid; the calf and the young lion shall browse together, with a little child to guide them. The cow and the bear shall be neighbors, together their young shall rest; the lion shall eat hay like the ox. The baby shall play by the cobra’s den, and the child lay his hand on the adder’s lair. ~Isaiah 11Paul prays for the the Roman believers to be at peace with each other.
May the God of endurance and encouragement grant you to think in harmony with one another. ~Romans 15Lest we get discouraged about the apparent lack of peace among Christians, the Gospel bluntly tells us how this is to be achieved. John the Baptist warns us to,
“Repent, for the kingdom of heaven is at hand!" and "produce good fruit as evidence of your repentance." ~Matthew 3That's it. Unless we actually repent and turn away from our sinful human nature, there will *be* no peace.