udaism, Christianity and Islam are often referred to as "sister religions" because they are closely related. However, several pronounced differences tend to alienate the three over the course of history, inducing each to alternate between periods of persecution and tolerance, even to today. Age, founder, population of believers, culture of origin, documentation, and differing views on the Messiah all factor in determining the differences and similarities between these three world religions.To begin, Judaism is the oldest of the three, more of a "mother religion." During the Roman occupation of the traditional Jewish homeland, Christianity came into being. Six hundred years later, Islam formed in the Middle East. All three religions base their calendar on an important event in their respective histories. The Jewish people begin their calendar at the creation of the world by the Creator. The Christians and Muslims, however, begin their calendars with an important event in the life of their founders. For Christians, it was his birth, and for Muslims, his pilgrimage. The Christian calendar is widely used today all over the world, and most especially in the west, while usage of the calendars of the other two is restricted to followers of each religion. Secondly, Abraham founded the Jewish religion by making a covenant with his God that would apply to all of his descendants. Jesus Christ founded Christianity. Born Jewish, Christ grew up questioning his religious upbringing and as an adult preached his own version. After his Crucifixion and supposed resurrection, Christians believed that his life fulfilled the original covenant and began a new era in which Christ's teachings were law. Islam is closer to Judaism in that both consider Jesus a prophet. Muslims believe that their founder, Muhammad, was the last prophet.In addition, Christianity incorporates about one third of the entire world's population as followers, divided into ...