There are many atemporal strands within Christianity. Every century and epoch in history has its own non-rational manifestations like this. If there was a first manifestation, an original birth of the “timeless,” a Christian might say that it was the person of Jesus of Nazareth, an immaculate conception through the Virgin mother, Mary.
Jesus’ followers were disciples who were committed to his teachings and the belief that he was the Savior, the Son of God, and the Jewish Messiah who had been prophesied, or foretold, in the Hebrew scriptures. He was referred to as Immanuel, which means “God with us.” More often he was called Christ, the Greek word for messiah, or “anointed one;” thus the name Jesus the Christ or Jesus Christ.
Followers believe that, as the Son of God, he came to reconcile humankind to God. As God himself in human form, his life, death, and resurrection served to bridge the worlds of the human and the divine. According to the doctrine of original sin, which was elaborated well after his death, he came for the remission of sins to offer everlasting life to all who believed in him as Christ, Lord and Savior.
Most denominations of Christianity today accept the doctrine of the Trinity, which is based on the conception of one god manifested in three distinct persons: God the Father, God the Son, and God the Holy Spirit. These three persons are known as the hypostases.
Prior to these councils many of the writings of Christian theological concerns were done by early apostolic fathers believed to have contact with the Twelve Apostles. In general, they stayed very close to scripture, which, most agreed, did not express the doctrine of the three persons of God. Following this line of belief, the school of Arianism developed in the third century based on a priest from Egypt named Arius. This teaching held that Jesus, although the Son of God, was still subordinate to God, not co-equal, not co-eternal, yet distinct as the formal Trinitarian doctrine would later state in the fourth century.
This problem of the same yet different just didn’t work for many people. However, in the early fourth century, in 325, the first ecumenical council was held in Nicaea, which is in present-day Turkey. One of the main purposes was to resolve the Arian controversy, and the result was that Arius was condemned as a heretic. Another result of the council was near-unanimous agreement on what would become the Nicene Creed, which includes the formal doctrine of the Trinity.
At this first council, the issue of Jesus’ divinity was agreed upon, and at the Council of Constantinople in 360, the doctrine of the Holy Spirit would be addressed. This solidified the Nicene Creed and the formal Trinitarian doctrine. This great mystery of the Christian faith is recognized by most churches, including the Roman Catholic, Eastern Orthodox, Anglican communion, and many, many Protestant denominations.
Source: This work is adapted from Sophia author Ted Fairchild.