Each of these three religions trace their origins back to Abraham, who became a nomadic tribal chieftain living in Southwestern Asia. Abram received a message from God to leave his homeland, Ur, and move into a land called Canaan. Here Abram changed his name to Abraham. God revealed himself to Abraham in a series of messages and visitations.
The 10 commandments were given to Moses on Mt. Sinai directly by God who carved the stone tablets during a 40 day period while Moses was sojourning on the mountain with God in a cloud that covered the mountain. The 10 commandments given by God to the Hebrews while they were wandering in the desert between Egypt and Israel for 40 years is the basis of the Torah and the 613 Jewish laws.
Christianity traces its origins back to Abraham and prophecies in the Jewish books of the Old Testament. Jesus is the promised messiah that was sent by God to earth. God is revealed to Jesus' followers through parables and miracles. Jesus' death on a Roman cross and resurrection on the third day are the basis of the Christian religion. According to Christianity, Jesus ascended to heaven to be with God and sent the Holy Spirit 5 weeks after his ascension to be with the Christian believers until his triumphant return to earth on the Last Day.
Islam traces its origins back to Abraham through Hagar and her son Ishmael. The prophet Mohammad received the revelation from the angel Gabriel which is contained in the text of the Koran.
The concept of revelation is that God reveals himself to humanity through self-disclosure or revelation of himself to human beings. God has revealed himself to the various prophets of each of these monotheistic faiths through direct contact. The historical narrative or dictations of these encounters with God are known as "the Book". The Jews have the Torah, The Christians have the Holy Bible, and the Muslims have the Koran.