The Canons of the Synods of Sardica, Carthage, Constantinople, and Carthage Under St. Cyprian, Which Canons Were Received by the Council in Trullo and Ratified by II. Nice 64Canon XLI.

That by men who are fasting sacrifices are to be offered to God.

That the Sacraments of the Altar are not to be celebrated except by those who are fasting, except on the one anniversary of the celebration of the Lord's Supper; for if the commemoration of some of the dead, whether bishops or others, is to be made in the afternoon, let it be only with prayers, if those who officiate have already breakfasted.