St. Augustine: The Church as Sign
‘They drank,’ he [Paul] said, ‘of the spiritual Rock that followed them, and that rock was Christ.” Thus the bread, thus the drink. The rock was Christ in sign; the real Christ is in the Word and in flesh …. But this is what belongs to the virtue of the sacrament, not to the visible sacrament; he that eats within, no without; who eats in his heart, not who presses with his teeth …. Believers know the body of Christ, if they do not neglect to be the body of Christ. Let them become the body of Christ, if they wish to live by the Spirit of Christ. None lives by the Spirit of Christ but the body of Christ …. I call that a spirit which is called the soul; that whereby it consists that you are man, for you consist of soul and body. And so you have an invisible spirit and a visible body …. My body of course lives by my spirit. Would you also then live by the Spirit of Christ? Be in the body of Christ …. He that would live has a place to live … Let him draw near, let him believe; let him be embodied, that he may be made to live. Let him not shrink from the compact of members …. And thus He [Christ] would have this meat and drink to be understood as meaning the fellowship of His own body and members, which is the holy Church in his predestinated, and called, and justified, and glorified saints and believers. (Lectures on the Gospel According to St. John 6:41-59).