You'll often find Early Church Fathers affirming the symbolism of the Eucharist, which is because the Eucharist is symbolic.
The species of bread and wine physically resemble the Body and Blood of Christ. Likewise, in giving Himself to us under the species of bread and wine, Jesus signals that He's the One who sustains us and nourishes us.
The Church Fathers also pointed out that bread and wine are metabolized. That in eating them, they become part of your body. So in eating the Flesh and Blood of Christ, the Living Bread and Wine in the Eucharist, we are "metabolized," so to speak, into the Body of Christ. This is what Paul seems to allude to in 1 Cor. 10:17.
So someone saying that the Eucharist is symbolic isn't problematic. Baptism is also symbolic, since the form of water symbolizes visibly what's done invisibly. It's only problematic if they say that it's ONLY symbolic.
Let's take those Fathers that seem to appear adhered only to the symbolic nature of the Eucharist:
I. Tertullian
This is from
Chapter 19 of On Prayer:
Quote:
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[TD="class: alt2"]Similarly, too, touching the days of Stations [these were fasting days], most think that they must not be present at the sacrificial prayers, on the ground that the Station must be dissolved by reception of the Lord's Body. Does, then, the Eucharist cancel a service devoted to God, or bind it more to God? Will not your Station be more solemn if you have withal stood at God's altar? When the Lord's Body has been received and reserved each point is secured, both the participation of the sacrifice and the discharge of duty.[/TD]
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So Tertullian acknowledges the Eucharist as the Lord's Body, and says it's offered at "God's altar." He also calls it a participation in the Sacrifice. Protestants deny all three of these things.
II. Hippolytus
In
this fragment of his writings, Hippolytus argues for the Real Presence on the basis of Proverbs 9:1-6:
Quote:
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[TD="class: alt2"]And to those that want understanding she said"—that is, to those who have not yet obtained the power of the Holy Ghost—"Come, eat of my bread, and drink of the wine which I have mingled for you;" by which is meant, that He gave His divine flesh and honoured blood to us, to eat and to drink it for the remission of sins.[/TD]
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III. Clement of Alexandria
In
Book II, Chapter 2 of the Paedagogos, Clement writes:
Quote:
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[TD="class: alt2"]And the blood of the Lord is twofold. For there is the blood of His flesh, by which we are redeemed from corruption; and the spiritual, that by which we are anointed. And to drink the blood of Jesus, is to become partaker of the Lord’s immortality; the Spirit being the energetic principle of the Word, as blood is of flesh.
Accordingly, as wine is blended with water, so is the Spirit with man. And the one, the mixture of wine and water, nourishes to faith; while the other, the Spirit, conducts to immortality. And the mixture of both— of the water and of the Word— is called Eucharist, renowned and glorious grace; and they who by faith partake of it are sanctified both in body and soul. For the divine mixture, man, the Father's will has mystically compounded by the Spirit and the Word. For, in truth, the spirit is joined to the soul, which is inspired by it; and the flesh, by reason of which the Word became flesh, to the Word.[/TD]
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That's about as clear as you can get, I think.
So, as you can see, all of the Church Fathers quoted believed that the Eucharist symbolized Christ, and that the Eucharist was the Body and Blood of Christ. Catholicism affirms both of these propositions, Protestantism doesn't. So it's hard to see these Fathers as being a challenge to the Catholic side.