Christianity establish the criteria unambiguously in the Apostles Creed which proceeded from the Great Commission. First of in the Interrogatory Creed Of Hippolytus in 215 AD and, in response to heresies and controversies, clarified and codified in 325 AD at Nicea in the Nicene Creed which established the baseline for Canon. If you do not adhere to the entire Apostles Creed you simply are not Christian.
Does the Nicene Creed include the Gospel of your salvation? Because if it doesn’t then it doesn’t matter what else it says. Without the Gospel of your salvation, you simply cannot be saved. And to be saved is to be a Christian.
Include the Apostles Creed to the previous post.