H/T: St. George San Diego (here)
The time to arrive for any Divine Service is before it is scheduled to begin. Sadly, it has become the custom of most Orthodox Christians to come to Church late. We are not speaking here, about occasional tardiness due to unforeseen circumstances, but the habitual practice of being late due to a lack of concern for being on time.
Does it really matter? Evidently, not in the mind of many, however not only do we hinder our own spiritual growth by consistently showing up late but, we also disturb our brothers and sisters in Christ who arrived on time and are already prayerfully communing with God. Hence, we should make the effort to arrive a few minutes early not simply to physically prepare ourselves but, more importantly, to shed the worldly baggage we bring with us — to “lay aside the earthly cares” — which, whether we are aware of it or not, has a profound impact on all those around us. Such faithful action not only nourishes our own soul, but sends an important message to our children, visitors and inquirers alike. Think of how odd it appears to visitors who, more often than not, arrive early for Church, and find the place almost empty.
Brothers and sisters, it is absolutely vital that we constantly remind ourselves of the great blessing we’ve been given by God in Holy Orthodoxy! An Orthodox Church is that part of God’s creation, which has been set apart and “reclaimed” for the Kingdom of God. Within its walls the heavenly God dwells and moves; the heavenly and earthly realms meet; Angels assist the Priest during the Divine Liturgy and Saints and members of the Church Triumphant join with the Faithful in the Divine Services. Coming into the Church, we, as it were, leave this world and enter the heavenly realm. Who would want to be late for that?
Given these very significant spiritual realities, beloved, let us begin to approach the Divine Services with a new found attitude of awe and reverence. Do we not make every effort to be to our jobs and secular appointments on time? How much more effort then, should we make to arrive punctually at our meeting with the heavenly realm?
Source: Fr. Luke Hartung Blog: The Dormition of the Theotokos Serbian Orthodox Mission