Why Were Only Four Gospels Included in the Christian Bible?

In the second century C.E., a Christian teacher named Marcion argued that only Mark and some of Paul’s letters truly represented Jesus’ teachings. For Marcion, all other versions of the Gospel were too Jewish; he did not believe that any part of the Jewish Bible should be considered Holy Scripture. Other Church leaders argued that not one, but four gospels were to be considered Holy Scripture--the gospels of Matthew, Mark, Luke, and John--and Marcion was declared a heretic.
Over the next few centuries, culminating with the Council of Nicea in the fourth century, Church leaders worked on establishing “orthodox” Christianity. The texts included in the New Testament reflect what they believed to be orthodox, reflecting Jesus’ true teachings. Even concerning the four gospels that we consider canonical today, Church leader engaged in heated debates about which to include in the Bible, and eventually some consensus formed around the four. Until the fourth century, however, it is clear that different Christian communities accepted as authoritative texts which would later be declared heretical or apocryphal (outside the canon).

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What Is the Feminine Divine in Christianity? 
The feminine divine is, as the terms implies, the idea of God in feminine terms. For example, in the Apocryphon of John, a text found in the Nag Hammadi Codex, God speaks to John, the brother of James, saying, “I am the One who is with you always, I am the Father, I am the Mother, I am the Son.” Another Nag Hammadi text describes the Spirit as “Mother of many,” and an even more radical text records, “I am the first and the last, I am the honored one and the scorned one, I am the whore and the holy one, I am the wife and the virgin, I am the mother and the daughter....”
While these texts were not included in the New Testament, and many were rejected as heretical, they show that some Christians in the first centuries did not see a problem speaking of God in feminine terms.
Many people are accustomed to thinking of God as a male figure, referring to God as He, Father, Master, or King. However, many Jewish, Christian, and Muslim theologians would point out that any theology in which God is not physical cannot insist on limiting God to a single gender. God is found to be "gendered" in the Bible partly because Greek and Hebrew are both gendered languages. 
While many other religions freely imagine God as female, the monotheistic religions tend to limit such descriptions. Additionally, many ancient writers probably had difficulty imagining the power of God in the possession of anyone but a male figure. However, some ancient biblical writers did imagine the divine as feminine. For example, Isaiah 66 describes God as a woman in childbirth and then as a nursing mother. Thus the feminine divine is already present in the Hebrew Bible. 
In the biblical Book of Proverbs, the concept of Wisdom (hokhma, a feminine noun) is personified as a woman (chapters 7-9). That book describes Wisdom as a power which pre-existed the world (3:19-20), and through which God created the world. For Christians, the feminine divine is present in the role of Sophia, the (feminine) Greek term for Wisdom. According to these texts, truth comes into the world through a combination of the male God and the female Sophia.
Contrary to Dan Brown's portrayal, there is no evidence that the feminine divine was intentionally snuffed out by early Church leaders, as hints of this aspect of the divine remain in Christian texts.   In a generally patriarchal society, it was not difficult for proponents of a patriarchal church to have their way as orthodoxy developed--but there's no evidence of the sort of intentional plot depicted in "The Da Vinci Code," in which a particular group of leaders conspired to oust Christians who wanted a greater role for women and the feminine divine.
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