The Two worlds in a Christian lives. – Charles Spurgeon

A Christian lives in two worlds at one and the same time — the world of flesh and the world of spirit. It is possible to do both. There are certain dangerous gases, which from their weight fall to the lower part of the place where they are, making it destructive for a dog to enter, but safe for a man who holds his head erect. A Christian, as living in the world of flesh, is constantly passing through these. Let him keep his head erect in the spiritual world, and he is safe. He does this so long as the Son of God is the fountain whence he draws his inspiration, his motives, en- couragement, and strength.— George Philip.