The New Age movement is a broad, social, spiritual, and intellectual movement based on the religious philosophy of the Far East. The people of the Far East have long been pantheistic in their understanding of reality. In other words, they believe that God is in all things, and that (in a sense) all things are divine, a part of God. This viewpoint allows people to define God in whatever manner they wish, an approach to religion that is very popular in our self-centered, individualistic culture.
One especially dangerous aspect of the New Age movement is the way it lends new meanings to traditional Christian terminology. Just as Hinduism has been able to assimilate all of the religious traditions in India, the pantheistic New Age movement is capable of deceiving many unwary Westerners.
New Age religion often utilizes altered states of consciousness to provide the existential basis for a satanic new faith. The widespread “recreational” use of psychoactive drugs has undoubtedly done much to stimulate interest in New Age mysticism during recent decades. For people who have been living as nominal Christians in a wasteland of materialism and scientific rationalism, the obviously spiritual, experiential side of New Age theology is powerfully seductive.
Two of the best books on the topic are A Crash Course On The New Age by Elliot Miller and The New Age Cult by Walter Martin.