Back to Basics: The Holy Eucharist

Of all seven sacraments, the Holy Eucharist is the most central and important to Catholicism, because of the staunch belief that the consecrated bread and wine are actually, really, truly, and substantially the body and blood, soul and divinity of Christ. For Catholics, the presence of Christ in the Holy Eucharist is not just symbolic, allegorical, metaphorical, or merely spiritual. It's real. That's why it's also called the Real Presence —because Christ really is present.

Catholicism for Dummies by John Trigilio