When we invite friends for a meal, we do much more than offer them food for their bodies. We offer friendship, fellowship, good conversation, intimacy, and closeness. When we say: "Help yourself ... take some more ... don't be shy ... have another glass," we offer our guests not only our food and our drink but also ourselves. A spiritual bond grows, and we become food and drink for one another other.
In the most complete and perfect way, this happens when Jesus gives himself to us in the Eucharist as food and drink. By offering us his Body and Blood, Jesus offers us the most intimate communion possible. It is a divine communion.