“How do you want the Master Christ to appear sweet and meek toward you, since you are becoming harsh with your fellow man and won’t forgive him? How can you lift your hands to Heaven? How will you move your tongue in words of prayer? How will you ask forgiveness? Furthermore, even if God wants to forgive your sins, you won’t allow Him, because you won’t forgive your neighbor.”
(St John Chrysostom ‘On Church Attendance’)