Therefore, as for you, let that remain in you which you heard from the beginning. If that which you heard from the beginning remains in you, you also will remain in the Son, and in the Father.

 Here are the Christian criteria of truth. There is an external test. All teaching must be in accordance with the tradition handed down to us in Scripture and in the Church. There is an internal test. All teaching must undergo the test of the Holy Spirit witnessing within our hearts. 