Unlike during a Roman Catholic nuptial Mass, Communion is not part of the Greek Orthodox wedding ceremony (
click here for an overview of an Orthodox nuptial liturgy).
If Catholics attend an Eastern Orthodox divine liturgy, during which Communion
is offered, there are circumstances (oulined in canon law) under which the Catholic Church will not object to Catholics receiving Orthodox Communion, but the Orthodox church
will strongly object to Catholics receiving their sacraments. So, ordinarily, no, Catholics should not receive Communion during an Orthodox divine liturgy.
Your profile indicates you are a Protestant. As Protestants do not hold the same belief in Christ’s presence in the Eucharist – body, blood, soul, and divinity – that Catholics and Orthodox share, they should be even more careful to refrain from receiving Catholic and Orthodox Communion (cf.
1 Cor. 11:27-30).
