St. Maximos the Confessor: If you wish not to fall away from the love of God...

If you wish not to fall away from the love of God, do not let your brother go to bed feeling irritated with you, and do not go to bed yourself feeling irritated with him. 

Reconcile yourself with your brother, and then come to Christ with a clear conscience and offer Him your gift of love in earnest prayer (cf. Matt. 5:24).

St. Maximos the Confessor