Origen deals with the question of the kidneys in his exegetical works written on Old Testament books. The two major topics of these texts are the cultic laws and sacrifices on the one side and the inner parts of the human being and its metaphoric sense on the other. Origen uses the word of "kidneys" in the following senses: 1) symbol of corporeal matter in Christ, 2) sacrifice for the sins in opposition of thank-offering, 3) inner conviction in opposition of pronounced word, 4) passive part or function of the soul, 5) desirous part or function of the soul, 6) male's procreative power, seat of spermatogenesis, 7) impious thought, 8) place of the birth of the fear, 9) seat of the innate seeds and roots of good and bad thoughts. In the newly rediscovered Second Homily on the Fifteenth Psalm Origen uses his theory of homonymy, and in his interpretation he follows an out-of-day medical theory criticized by Galen. For Origen the kidneys are the seats of man's sexual potency. Spiritual kidneys are the places of spiritual procreative power, i. e. seeds and roots of good and bad thoughts, and these Origenian ideas of the Second Homily on the Fifteenth Psalm strongly modify the conventional picture of his anthropology.