What was that citation and when. Was not in the first century.
So if the Christians were being accused of cannibalism, how did they respond? Justin Martyr dealt with several of the accusations against Christians in his First Apology (written circa 150 A.D.) which was addressed to the Roman Emperor Antoninus Pius. Debunking them clearly and thoroughly. He answers the charge of atheism and child sacrifice. However, he does not answer the charge of cannibalism which is strange considering an audience with the Emperor is the perfect time to respond to this charge (especially if it is merely a symbol). Instead, Justin affirms the reality of Christ in the Eucharist while describing the second-century Christian gatherings:
And this food is called among us Εὐχαριστία [the Eucharist]… For not as common bread and common drink do we receive these; but in like manner as Jesus Christ our Saviour, having been made flesh by the Word of God, had both flesh and blood for our salvation, so likewise have we been taught that the food which is blessed by the prayer of His word, and from which our blood and flesh by transmutation are nourished, is the flesh and blood of that Jesus who was made flesh. For the apostles, in the memoirs composed by them, which are called Gospels, have thus delivered unto us what was enjoined upon them; that Jesus took bread, and when He had given thanks, said, “This do in remembrance of Me, this is My body;” and that, after the same manner, having taken the cup and given thanks, He said, “This is My blood;” and gave it to them alone.