You might say to yourself, “How can we know that the Lord did not speak the message?” If what the prophet proclaims in the name of the Lord is not true and it does not happen, then the message was not proclaimed by the Lord. The prophet has spoken presumptuously, you should not fear him.
Let what you heard from the beginning remain in you. If what you heard from the beginning remains in you, then you will remain in the Son and in the Father.