His head and [his] hairs [were] white like wool, as white as snow; and his eyes [were] as a flame of fire;
And his feet like unto fine brass, as if they burned in a furnace; and his voice as the sound of many waters
This is the religion with the most adherents. Christianity is a fusion of Jewish Messianic ideas (the savior who comes to Earth to save humanity) and Greek Gnostic rites (the God who dies, goes to hell and rises after three days).
It appears to be the brainchild of Saul (known to Christians as Saint Paul) who combined the two threads and removed the strict dietary requirements and circumcision of Judaism.
Christianity is first mentioned in historical documents at the end of the 1st century AD. The Christian Bible is made up of the Jewish parts (The Old Testament) and the newer part written originally in Greek and called The New Testament). A meeting of the Church during the early part of the second century AD finalized which books were to be included in the New Testament.
Christians believe in a single god that has appeared on Earth as a historical character called Jesus Christ in order to save the world after the first man, Adam (actually a Hebrew word meaning man), had condemned the world by disobeying God.
There is also an entity called the Holy Spirit. These three make up what is called the Holy Trinity. This is actually one of the most complex theological ideas in any religion. It is one of the reasons that the monotheistic Islam made so much progress during the 7th century.
Christianity preaches love and forgiveness but its adherents have often fought against non-Christians and fellow Christians throughout history. There are hundreds of sects (or denominations as the faithful call them). The major ones are Orthodox (ritualistic but with no Pope - practiced mainly in the Middle East and Eastern Europe), Catholic (controlled by the Pope, contains many saints and pilgrimage places - practiced mainly in Southern Europe and Latin America), and the Protestants (less ritual orientated - practiced in Northern Europe, Northern America and Oceana). The liturgical languages vary from Latin, Greek, Russian to the vernaculars of various countries). The Orthodox sect was the original. Catholics split around the 4th century and Protestants around the 1600s.
The main rite of Christians is the symbolic one of drinking wine and eating bread. This is supposed to signify the blood and body of the Christ. Baptism and the sign of the cross are also widely practiced. The latter was a late addition since early Christians used the fish as their symbol. The Greek for fish (ICHTHOS) was the initials of the phrase Jesus Christ, Son of God, Savior.
Many of these rites were derived from the Essenes, the pre-Christian sect who wrote the Dead Sea Scrolls.
As with the Jews, Jerusalem is a holy city but Bethlehem, Nazareth and Rome come close behind.
Christian festivals are either derived from their Jewish counterparts (Easter) or from Roman festivals taken over by the faith (Christmas). As Christianity moved into northern Europe many local rites were incorporated (Christmas trees, Santa Claus, hot cross buns). Many of the holiest shrines of Christianity are on sites previously occupied by Roman and Greek temples. The birthplace of Jesus is on the site of a temple to Adonis, for example.
Many historians do not consider that Jesus Christ was a historical character. The name Jesus comes from the Aramaic Yashu’a (which means savior) and the Greek Christos (anointed), so the name actually means anointed savior.