By St. Barasanuphios the Great
If you cannot discourse about faith, do not try to. If a man is firm in faith he will never be confused in discussions and disputes with heretics or unbelievers, because he has in him Jesus, the Lord of peace and quiet. After a peaceful discussion, such a man can lovingly bring many heretics and unbelievers to the knowledge of Jesus Christ our Savior. As for you, since discoursing on some subjects is beyond you, keep to the royal road, that is to the faith of the 318 holy fathers (Nicene Creed), into which you were baptized. It contains everything stated exactly for perfect understanding. But most of all have attention in yourself, meditating on your sins and on how you will be received by God.