 In subsequent books he pursued specific topics in New Age spirituality such as claims that Jesus spent his adolescent years studying among Hindu and Buddhist teachers in India and Tibet in "Revealing the New Age Jesus".The phenomena of near-death experiences and the claims of Betty Eadie about the afterlife were the subject of his analysis in "Deceived by the Light".In the 1990s, Groothuis began to write about the cultural shifts associated with postmodern philosophy in his book "Truth Decay", as well as to formulate responses to those shifts via Christian apologetics.