The movement represented a reaction against the rigid theology and formal worship of the traditional churches. Glossolalia, or speaking in tongues, often occurs. Pentecostalists believe in the literal word of the Bible and faith healing. They disapprove of alcohol, tobacco, dancing, the theater, and gambling. It is an intensely missionary faith, and in-person recruitment as well as through television has been very rapid since the 1960s. Worldwide membership is more than 20 million, and it is the world's fastest growing sector of Christianity.