Ash Wednesday

Per the Office of Readings for April 6th, 2013 (Saturday in Easter Octave), From the Jerusalem Catechesis (attributed to Cyril of Jerusalem):

Therefore, it is with complete assurance that we receive the bread and wine as the body and blood of Christ. His body is given to us under the symbol of bread, and his blood is given to us under the symbol of wine, in order to make us by receiving them one body and blood with him. Having his body and blood in our members, we become bearers of Christ and sharers, as Saint Peter says, in the divine nature.

Though it may at first glance stir confusion, the reference to "symbol" is what the Church of today refers to as "accidents" regarding the doctrine of transubstantiation.  This is confirmed 3 ¶s later, whereby Cyril states:

Way back when Octaves were still En Vogue (outside of Easter, Epiphany, etc.), the 3rd nocturn for the 6th feria (in the Octave of Corpus Christi) featured a sermon by St. Augustine (27th Tract on the Gospel of John) that dealt in some of the same aspects of the sacrament:

But most of those who were present, by not understanding Him, were offended; for in hearing these things, they thought only of flesh, that which themselves were. But the apostle says, and says what is true, To be carnally-minded is death. _Romans 7:6 The Lord gives us His flesh to eat, and yet to understand it according to the flesh is death; while yet He says of His flesh, that therein is eternal life. Therefore we ought not to understand the flesh carnally.

...

They understood but as they pleased, even after the manner of men, that Jesus was able, or that Jesus meant, to give that Flesh wherewith the Word is clothed on, as it were, in slices, to them that believe on Him. And they said "This is an hard saying who can hear it?"

One of the most excellent catechetical resources titled "The Real Presence" (www.therealpresence.org) sheds an ample amount of light on the subject:

Earlier I mentioned confusion among Catholics about the implications of Christ's Eucharistic presence, and I posed the question: Do we receive (for instance) Christ's head and arms and feet? Many today would be uncomfortable with an affirmative answer, which would savor, to them, of a grossly materialistic view of the Real Presence. Yet it is the right answer. Suppose we didn't receive those parts: then the same would have to be said of all the other parts of his body. So there'd be nothing left! We would not be receiving his body. As the Catechism of the Council of Trent says, in this sacrament are contained "… all the constituents of a true body, such as bones and sinews…." [7]

...

Think of quantity. It is the fundamental accident, as we have noted. Normally it is the accident whereby its substance occupies a place; but the essential thing it does is to give the substance parts. And in the Eucharist all the parts of Christ's body are present and are situated relatively to each other. But because of the unique way in which the quantity is there—in the manner of substance—the parts are not spread out in relation to the surrounding place. To put it another way: substance as such is distinct from quantity, and it occupies a place only because of its quantity. But when quantity becomes present through transubstantiation it exists in the manner of substance, and therefore without actual extension.

An insidious obstacle to an understanding of the Real Presence (of course it can never be fully understood in this life) is the almost overwhelming influence of the imagination. The imagination is a picture-making power which accompanies all our thinking; but it is distinct from the intellect and it deals only with what can be seen, touched or in some way sensed. The deeper level of being, accessible to the intellect, is beyond the reach of the imagination. However, the imagination still provides images, and these easily mislead us.

For example, the statement that Jesus is in the Eucharist with all his parts may bring a picture into the imagination of a tiny body small enough to fit in the host. We know it's not like that, but the imagery can still distort one's thought, or block it, or even tempt one to discard the Real Presence in favor of a symbolical or "spiritual" presence.

May our Lord Jesus Christ continue to enlighten us this Easter Season & conform us to His image in this, the wonderful sacrament of His enduring love.

_{[7] Catechism of the Council of Trent, p. 233.}