The study of the psyche, Greek for "soul." Generally, modern psychology has been defined variously as the study of human nature, including the ways we think and behave, and the conditions that influence them.
We currently have no entry on the subject, but you may wish to read:
Jeffrey H. Boyd, "Biblical Psychology: A Creative Way to Apply the Whole Bible to Understanding Human Psychology," Trinity Journal 21NS (2000): 3-16.
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