Epistles of Ignatius

The Lord has made my burdens light and easy since I learned that you are in peace, living in harmony both physically and spiritually. "I therefore, the prisoner of the Lord, urge you to walk worthy of the calling you have received," guarding against the heresies of the wicked one that have invaded us, leading to the deception and destruction of those who accept them; but that you pay attention to the doctrine of the apostles, and believe both the law and the prophets: that you reject every Jewish and Gentile error, and neither introduce a multitude of gods nor deny Christ under the pretense of maintaining the unity of God.