As for you, the anointing which you received from him remains in you, and you don't need for anyone to teach you. But as his anointing teaches you concerning all things, and is true, and is no lie, and even as it taught you, you will remain in him.

 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. 