Isaiah 11:9 reads: "They will not hurt or destroy on all my holy mountain; for the earth will be full of the knowledge of the LORD as the waters cover the sea."
Just before this verse, there is a lengthy description of the peaceful kingdom - a time and a place in which the wolf shall lie down the lamb and the nursing child shall play over the hole of the asp. All of the natural world and every part of creation shall live in harmony and in love.
I know - it sounds like a utopian pipe dream. But it's only the reality of the Kingdom of God on earth.
What strikes me is how it is knowledge of the Lord that creates the peaceful kingdom. In the Old Testament, knowing somebody means having sexual intercourse with them. So having "knowledge of the LORD" is a wonderful and insightful word play. In other words, having a deeply intimate and loving relationship with the Lord is a sign of God's reign. How delightfully...provocative.