Food for thought: A monstrous substitution

From The Pursuit of God by A.W. Tozer:

There is within the human heart a tough, fibrous root of fallen life whose nature is to possess, always to possess. It covets things with deep and fierce passion. The pronouns my and mine look innocent enough in print, but their constant and universal use is significant. They express the real nature of the old Adamaic man better than a thousand volumes of theology could do. They are verbal symptoms of our deep disease. The roots of our hearts have grown down into things, and we dare not pull up one rootlet lest we die. Things have become necessary to us, a development never orginally intended. God's gifts now take the place of God, and the whole course of nature is upset by the monstrous subsitution.