Does prayer have an effect on healing? This doctor says it's one of the best-kept secrets in medical science. Dip into the Oprah Show archive and watch Dr. Larry Dossey discuss the power of prayer this Sunday at 12 p.m. ET/PT on OWN. Plus, watch from anywhere in the world on Oprah.com, Facebook.com/OWNTV and Facebook.com/SuperSoulSunday.

Before then, look back at Oprah's Soul Series interview with Dr. Dossey:
Part 1
Part 2