The Bible contains 13 references to wolves, usually as metaphors for greed and destructiveness. The Book of Genesis was interpreted in Medieval Europe as stating that nature exists solely to support man, who must cultivate it, and that animals are made for his own purposes. By this perspective, nature was only acceptable if controlled by man. The wolf is repeatedly mentioned in the scriptures as an enemy of flocks: a metaphor for evil men with a lust for power and dishonest gain, as well as a metaphor for Satan preying on innocent God-fearing Christians, contrasted with the shepherd Jesus who keeps his flock safe. The Roman Catholic Church often used the negative imagery of wolves to create a sense of real devils prowling the real world. Quoting from Leviticus and Deuteronomy, the Malleus Maleficarum states that wolves are either agents of God sent to punish sinners, or agents of the Devil sent with God's blessing to harass true believers to test their faith.