Holy Eucharist - Blessed Sacrament teachings
Pope Leo the GreatSermon, 91:3
"Dearly-beloved, utter this confession with all your heart and reject the wicked lies of heretics, that your fasting and almsgiving may not be polluted by any contagion with error: for then is our offering of the sacrifice clean and oar gifts of mercy holy, when those who perform them understand that which they do. For when the Lord says, "unless ye have eaten the flesh of the Son of Man, and drunk His blood, ye will not have life in you,' you ought so to be partakers at the Holy Table, as to have no doubt whatever concerning the reality of Christ's Body and Blood. For that is taken in the mouth which is believed in Faith, and it is vain for them to respond Amend who dispute that which is taken."
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