It is the duty of every Orthodox Christian to partake of Holy Communion, since it is by this Sacrament that we become one with Christ and with one another. We ought to partake regularly, if possible whenever the Divine Liturgy is served, and be fasting from midnight of the day on which Holy Communion is to be received. Regular reception of Holy Communion is especially beneficial – although this must not become the cause of disrespect towards the Body and Blood of Christ.
For worthy participation of the Sacrament, we ought:
1) to have an unshakeable faith in Christ our Saviour and in the teachings of the Orthodox Church;
2) to attend church regularly, and to pray regularly;
3) to cleanse our consciences from evil deeds, hate and injustice, forgiving all those who have injured us from the depths of our hearts; and we ought also to have peaceful relations and charity even towards those who are our enemies.
Holy Communion may only be received by members of the Orthodox Church – that is to say, those who are baptised and members in good standing of Churches in Eucharistic communion with the Ecumenical Patriarchate or a patriarchate in communion with our Mother Church.
Saint Justin Martyr on Holy Communion
This food we call the Eucharist, of which no one is allowed to partake except one who believes that the things we teach are true, and has received the washing for forgiveness of sins and for rebirth, and who lives as Christ handed down to us. For we do not receive these things as common bread or common drink; but as Jesus Christ our Saviour, being incarnate by God’s Word, took flesh and blood for our salvation, so also we have been taught that the food consecrated by the Word of prayer which comes from him, from which our flesh and blood are nourished by transformation, is the flesh and blood of that incarnate Jesus.