The National Black Church Initiative has voted to break its connection with the Presbyterian Church USA following its recent approval of same-sex marriage.

The NBCI is a faith-based group of over 34,000 churches in 15 denominations with 15.7 million African American members. The initiative announced its break with the Presbyterian Church USA today, citing that the PCUSA is preaching another Gospel.

"NBCI and its membership base are simply standing on the Word of God within the mind of Christ," said NBCI president Rev. Anthony Evans in a statement. "We urge our brother and sisters of the PCUSA to repent and be restored to fellowship."

The Presbyterian Church USA voted earlier this month to officially change the definition of marriage in the church's constitution to include same-sex marriage. The wording in the bylaws changed the marriage definition from between "a man and a woman" to "two people, traditionally a man and a woman."

The PCUSA is the largest of the country's Presbyterian denominations with about 1.8 million members, but this change in the constitution has led to a mass exodus of members in just the last week.

"We definitely will see another wave, a sizable wave, of conservative folks leaving," said Paul Detterman, national director of The Fellowship Community, a group of conservatives who have stayed in the PCUSA.

The Brighton Presbyterian Church is one church that does not agree with what the PCUSA voted into its constitution. "Our congregation has long been a more traditional congregation," said Tim Luddy, pastor of Brighton Presbyterian. "When it comes to issues of abortion and same-sex marriage, we believe that the Bible speaks clearly to us on that.

"We hold very dear to us the idea that God's word is our authority when we go about the work he has called us to do. It's that simple."

Other denominations that have made same-sex marriage officially allowed include the Episcopal Church, the United Church of Christ, the Quakers, the Unitarian Universalist Association of Churches, the Evangelical Lutheran Church and, in Judaism, the Reform and Conservative movements.

But the National Black Church Initiative urges all true Christians to not fall against the Word of God for the sake of what's current a popular trend in society.

"No church has the right to change the Word of God," the NBCI states. " By voting to redefine marriage PCUSA automatically forfeits Christ's saving grace. There is always redemption in the body of Christ through confession of faith and adhering to Holy Scripture.  In this case, PCUSA deliberately voted to change the Word of God and the interpretation of holy marriage between one man and one woman.  This is why we must break fellowship with them and urge the entire Christendom to do so as well."

Galatians 1:8 is a perfect example of where the Bible warns against such tribulations. "For if he that cometh preacheth another Jesus, whom we have not preached, or if ye receive another spirit, which ye have not received, or another gospel, which ye have not accepted, ye might well bear with him...For such are false apostles, deceitful workers, transforming themselves into the apostles of Christ. And no marvel; for Satan himself is transformed into an angel of light."