“The Eucharist belongs to and is shared by those who have been baptized into the Church and who hold a common faith in the bond of love. Thus, only those Orthodox Christians in full communion with the Church may partake of the Holy Gifts. For the Orthodox, the Eucharist is not an instrument or means for achieving Christian unity, but the very sign and crowning of that union based on doctrinal truths and canonical harmony already held and possessed in common.
The Eucharist is both a celebration and a confession of the faith of the Church. Hence it is not possible to approach Holy Communion by way of hospitality. It is expected that every baptized and chrismated Orthodox adult, child, and infant be regular and frequent recipients of the Divine Mysteries. It is presupposed that adult and children communicants have fasted from the evening meal prior to receiving Holy Communion at the morning Eucharist. However, care must be exercised never to consider Holy Communion a reward for pious feelings and actions, but as a gift of the Lord to the members who comprise his Body, the Church.”
(Alkiviadis C. Calivas, Essays in Theology and Liturgy: Volume 3, pg. 172)