East: Bishop St. Ignatius the Martyr of Antioch says in 110 [Epistle to the Smyrnaeans 7:1],
They [heretics] abstain from the Eucharist and from prayer, because they confess not the Eucharist to be the flesh of our Savior Jesus Christ, which suffered for our sins, and which the Father, of His goodness, raised up again. Those, therefore, who speak against this gift of God, incur death in the midst of their disputes.West: Bishop St. Irenaeus of Lyons says in 200 [Against Heresies 4:18:4-5],
But how can they be consistent with themselves, [when they say] that the bread over which thanks have been given is the body of their Lord, and the cup His Blood, if they do not call Himself the Son of the Creator of the world, that is, His Word, through whom the wood fructifies, and the fountains gush forth, and the earth gives "first the blade, then the ear, then the full corn in the ear" [Mk 4:28]. Then, again, how can they say that the flesh, which is nourished with the body of the Lord and with His Blood, goes to corruption, and does not partake of life?