Reject the vomit

The truth of the Unity of God has been delivered to thee: learn to distinguish the pastures of doctrine. Be an approved banker, holding fast that which is good, abstaining from every form of evil . Or if thou hast ever been such as they, recognise and hate thy delusion. For there is a way of salvation, if thou reject the vomit, if thou from thy heart detest it, if thou depart from them, not with thy lips only, but with thy soul also: if thou worship the Father of Christ, the God of the Law and the Prophets, if thou acknowledge the Good and the Just to be one and the same God . And may He preserve you all, guarding you from falling or stumbling, stablished in the Faith, in Christ Jesus our Lord, to Whom be glory for ever and ever. Amen.
St. Cyril of Jerusalem