The Longer Catechism of the Orthodox, Catholic, Eastern Church

“At the moment of this act the bread and wine are changed, or transubstantiated, into the very Body of Christ, and into the very Blood of Christ.”

“By the name holy tradition is meant the doctrine of the faith, the law of God, the sacraments, and the ritual, as handed down… from one to another, and from generation to generation.”

“The Church is a divinely instituted community of men, united by the orthodox faith, the law of God, the hierarchy, and the Sacraments.”

“They may be aided towards the attainment of a blessed resurrection by prayers offered in their behalf, especially such as are offered in union with the oblation of the bloodless sacrifice of the Body and Blood of Christ, and by works of mercy done in faith for their memory.”

“A Mystery or Sacrament is a holy act, through which grace… works mysteriously upon man.”