By St. John the Prophet
Question 758: If I do something against my brother and he grieves upon hearing about it, is it perhaps a good thing to hide the truth from him in order to stop the grief? Or is it better to admit my fault and ask for forgiveness?
Response: If he has clearly learned about it, and you know that the matter will be examined and revealed, then tell him the truth and ask for his forgiveness. For lying will only further provoke him. However, if he has not learned about it and will not examine the matter, then it is not improper to keep silent and not give occasion to grief.
For when the Prophet Samuel was sent to anoint David as king, he was also going to offer sacrifice to God. Yet, because he was afraid lest Saul learn about this, God said to him: "Take a heifer with you; and if the king asks you: 'Why did you come here?' tell him: 'I have come to sacrifice to the Lord'" (1 Sam. 16:2). In this way, by concealing one thing, which brought the wrath of the king, he only revealed the other.
You too, then, should be silent about that which causes grief, and the problem will pass.
From The Letters of Saints Barsanuphios and John; translated by John Chryssavgis.