"The infant will play near the hole of the cobra, and the young child put his hand into the viper's nest." NIV translation
Not only will this peace be between two people or two different kinds of animals, there will be total peace between man and all animals. This peace is so complete that the animal does not even guard their den anymore. Some may say: "That's not possible" but the One who created all things can do all things and I have personally seen God stop a mean dog in its tracks and cause it to smile.
"They will neither harm nor destroy on all my holy mountain, for the earth will be full of the knowledge of the Lord as the waters cover the sea." NIV translation
Everyone will be able to see the effect of Jesus as there will be no more violence in this kingdom.
"In that day the Root of Jesse will stand as a banner for the peoples; the nations will rally to him, and his place of rest will be glorious." NIV translation
During this millennial reign, Jesus and His people will stand out as a bright beacon to the nations. The people will have one last chance to accept Him as their Lord and Savior and this chance is under ideal conditions as Satan has been removed from the earth.
"In that day the Lord will reach out his hand a second time to reclaim the remnant that is left of his people from Assyria, from Lower Egypt, from Upper Egypt, from Cush, from Elam, from Babylonia, from Hamath and from the islands of the sea." NIV translation
All of God's people will be drawn to be in His presence. They will all be together again in the holy city.
"He will raise a banner for the nations and gather the exiles of Israel; he will assemble the scattered people of Judah from the four quarters of the earth. Ephraim's jealousy will vanish, and Judah's enemies will be cut off; Ephraim will not be jealous of Judah, nor Judah hostile toward Ephraim." NIV translation
There are those who say that these events have already happened as they point to the establishment of the state of Israel. It is possible that this is in the process of happening but it cannot be completely fulfilled yet as there is not total unity within Israel even today. The good news is that Jesus will bring true peace and gather all of God's people together to reign for the thousand years.