He that gives an apology in behalf of the oppressed will find an advocate in his creator. He that gives his arm to the help of his fellow, will receive God’s arm instead of it. He that accuses his brother on account of his evil deeds will find God as his accuser. He that directs his brother in his inner apartment, cures his evil; he that accuses him before an assembly makes worse his wounds. He that cures his brother privately gives a proof of the strength of his love, but he who exposes him in the presence of his comrades betrays the force of his envy.
Mystic Treatises. Chapter 45: Profitable advice
St. Isaac the Syrian (7th Century)