At the same time, it is in disagreement with Christian self-description. Christian theology teaches that the Christian covenant with God is something much more particular than the covenant with Noah. Throughout the New Testament and in the course of Christian interpretation throughout tradition, Christianity sees itself as the successor of all the covenants made between God and humanity in all of scripture. Christianity has a covenant with God sealed in the blood of Jesus, whom we accept as the universal Messiah. As a result, we do not consider ourselves gentiles.
Gentiles are non-Jewish nonbelievers.
Our language gives us away on this. In the Roman Catholic Church we always consider our mission to be ad gentes to the nations. Once a person is incorporated into the Church, he or she shares, through the Christian covenant, in the heritage of Israel as well as the heritage of all humanity. We say that we are children of Abraham by adoption. Our theologies here are probably not reconcilable.