Divine Liturgy Etiquette

St. John Chrysostom writes thusly against those who in church create a disturbance and who depart from church before the completion of the Divine Liturgy:

Some do not approach Holy Communion with trembling but with commotion, shoving one another, burning with anger, hollering, scolding, pushing their neighbor, full of disturbance. About this, I have often spoken and will not cease to speak about this. Do you not see the order of behavior at the pagan Olympic games when the Arranger passes through the arena with a wreath on his head, dressed in a lengthy garment, holding a staff in his hand and the Crier declares that there be silence and order? Is it not obscene that there, where the devil reigns, there is such silence, and here where Christ invites us to Himself there is such an uproar. At the arena, silence, and in church, uproar! On the sea, calm, and in the harbor, tempest!

When you are invited to a meal, you must not leave before the others, even though you are satisfied before the others, and here while the awesome Mystery of Christ is being celebrated, while the priestly functions are still continuing, you leave in the middle of it and exit? How can this be forgiven? How can this be justified? Judas, after receiving Communion at the Last Supper [Mystical Supper] that final night, departed quickly while the others remained at the table. Behold, whose example do they follow who hurry to depart before the final thanksgiving?

(Homily on the Feast of the Epiphany)