Do not raise your voice in anger to anybody because “the servant of the Lord must not strive” (2 Timothy 2:24).
Do not hate anyone in your heart or else your prayer will not ascend to God “let not the sun go down upon your wrath” (Ephesians 4:26). Be kind and patient, humble and as a child in heart, because God said “And said, Verily I say unto you, Except ye be converted, and become as little children, ye shall not enter into the kingdom of heaven” (Matthew 18:3).
Do not be sad if something bad happens because of some shortcomings or defamation “the sorrow of the world worketh death” (2 Corinthians 7:10). Do not grieve for anything else but for your sins, because the rest is just dust in the wind. Do not raise your voice in anger to anybody because “the servant of the Lord must not strive” (2 Timothy 2:24). Do not utter any words of reproach, oath or gossip because your tongue is hallowed by spiritual chants and the praise of God.
(Translated from: Patericul Lavrei Sfântului Sava, Editura Egumenița, 2010, pp. 133-134)