Why does the Divine want to manifest Himself on earth in this chaos?
Because this is why He has created the earth, not for any other motive; the earth is He Himself in a deformation and He wants to establish it back again in its truth. Earth is not something separated from Him and alien to Him. It is a deformation of Himself which must once again become what it was in its essence, that is, the Divine.
Then why is He a stranger to us?
But He is not a stranger, my child. You fancy that He is a stranger, but He is not, not in the least. He is the essence of your being, not at all alien. You may not know Him, but He is not a stranger; He is the very essence of your being. Without the Divine you would not exist.