Communion

When one speaks of Communion in Matters of Faith and in Synodal Administration, it is either talking about Holy Communion, or the Eucharist, which is the Body and Blood of Jesus Christ that is given to Orthodox Christians every Divine Liturgy and is a Holy Mystery and Sacrament of the Church, or it is talking about Formal Eucharistic Communion which is a Formal Agreement between two or more Synods or Autocephalous Churches which Formally and Synodally join and cooperate together.

Formal Eucharistic Communion is Communion between two or more Synods or Autocephalous Churches based on the facts of their Common and Shared Confession of Faith and Formal Synodal Recognition of each other which allows each Synod's Laity and Clergy to partake in the Sacraments of each Synod in Formal Communion and Clergy to concelebrate with another Synod or multiple Synods. For example, most of the Patriarchates have established Formal Eucharistic Communion with each other so they formally recognize all the Patriarchates as being Orthodox, formally recognize both their Apostolic Succession and Sacraments as valid, each Patriarchate's Clergy can concelebrate with each others, and their Laity may take Communion in other Patriarchates.

Informal Communion is a less common term but a term which refers to an action in which a Synod may allow it's Laity to commune in another Synod (Whom Bishops recognize this other Synod's Validity and Orthodox Confession of Faith) but do not hold a Formal Eucharistic Communion with. For example, Synod A holds no Formal Eucharistic Communion with Synod C for some cirumstances however Synod A's Bishops recognize Synod C's Confession of Faith as Orthodox and their Sacraments and Apostolic Succession as valid so Synod A's Bishops allow or permit for their own Laity to partake in Synod C's Sacraments - Whether they need to out of Circumstance or for Oikonomic Reasons.

When a Synod or Autocephalous Church severs Formal Eucharist Communion with another Synod it is either known as a Severance of Communion, or a Schism depending on circumstance. This mean that the Synod severing Communion will now cease Formal Synodal Recognition and Cooperation of the other Synod, or Synods, and will most likely have its Laity cease partaking in the Sacraments of the prior parnter Synods. A suspension in Concelebration is usually not a ceasing or severance of Communion between two or more Synods but it rather means that Clergy and from one Synod may not concelebrate (Celebrate and Preform the Divine Liturgy with other Priests from another Synod) with another Synod, or Synods, and the Clergy may not partake in the Sacraments of the other Synod or Synods.