What is the Orthodox Church:
The Orthodox Church or Church of the East or Greek Orthodox Church is one of the congregations of believers in the Christianity.
The Orthodox Catholic Church was born from the definitive separation of the Christian Church in the schism of the year 1054. Before the schism, all Christian churches were under the jurisdiction of Rome which were completely separated from Rome in the year 1054 dividing into:
the Roman Apostolic Catholic Church or the Orthodox Catholic Church or the Orthodox Church or the Eastern Church
See also Schism.
The Orthodox Church, as its name suggests, is orthodox which means ‘right belief’ therefore it maintains the original creed without the alterations that the Roman Catholic Church introduced. Some of them are:
the Holy Spirit: Its origin is only from the father in the original version.
purgatory: The Orthodox Church says that souls after death go to the ‘final judgment’ instead of the purgatory of the Roman Catholic Church which was recently repealed.
the original sin It is a concept of the Roman Catholic Church. The Orthodox Church continues with the ancestral sin that refers to the force that induces us to lean towards evil.
the immaculate conception of the Virgin Mary: The Orthodox Church affirms that the Virgin Mary was born as a result of intercourse. Only Jesus, son of the Virgin Mary, is born of immaculate conception.
Due to Christian theology, which studies the word of God, the Christian Church began to have discrepancies in interpretation such as the concepts of the Trinity and the interpretation of the life and death of Jesus among other things, dividing into 3:
The Orthodox Catholic Church or Church of the East or Greek Orthodox Church Roman Catholic Church whose believers are called Catholics The Protestant Church whose followers are called Protestants
You may also be interested in reading about Christianity.