With over 2 billion adherents, Christianity is the world's most popular religion. Christianity, major religion founded in the first century CE on the life, teachings, and death of Jesus of Nazareth. It has grown to be the world's largest religion and, geographically, the most widely dispersed of all faiths. Only Christians recognize the Three-in-One God, making Christianity the only faith system in the world. The fact that all three Persons of the Three-in-One exist both now and forever is central to the Christian doctrine of the Trinity. In other words, God is now, has always been, and will always be Father, Son, and Holy Spirit, three Persons who are also One. People all over the world follow this religion and it encompasses strong beliefs and principles.