Early Muslims wrote extensively about human nature and called it Ilm-al Nafsiat or self-knowledge. In many cases, their works seem to be the original ideas for many modern day psychological theories and practices. What is interesting however is that a lot of what the early scholars wrote was blended with Islamic philosophy and religious ideas. This paper covers major contributions of prominent early Muslim scholars to psychology and outlines the challenges faced by today's Muslims in adapting to the Western theories. It also offers a few recommendations on the indigenization of psychology for Muslim societies interested in seeking the Islamic perspective on human behaviors.