Last month, it revealed plans to bring in somebody to minister to those who feel the Church of England and the Scottish Episcopal Church have become too liberal in their stance on homosexuality.
Addressing the issue on Premier's News Hour, Most Rev Peter Jensen, GAFCON's General Secretary and a former Archbishop of Sydney, said: "There are many issues that divide us, where we have diverse opinions, and that's OK - but some of them are so important that a stand has to be taken. A painful and costly stand.
"The Primates believe that this present matter is one of those things and the Bible is as clear as can be - that to embrace the view that the practice of homosexuality is OK is wrong according to the Bible.
"It's a very significant matter in our view and puts the authority of the Bible at stake."
It's unclear whether the bishop will be British or from overseas.
They'll be announced on Thursday - the day the Scottish Episcopal Church votes on whether to redefine marriage in order to oversee gay weddings.
It comes just weeks after it was announced Rev Jonathan Pryke from Jesmond Parish Church in the North East of England was made a bishop by the Reformed Evangelical Anglican Church of South Africa.
He will also provide oversight to churches who are unhappy with developments in the Church of England.