Venerable Fulton Sheen
“It would take pages to reveal the prefigurement of the Sacrament of the Eucharist in the Old Testament. Melchisedech offering bread and wine was a figure of Christ Himself, Who chose bread and wine the night of the Last Supper as the elements for both the sacrifice and the sacrament. The manna that fell in the desert was also a symbol of the Eucharist, which Our Blessed Lord said was Himself: “I myself am the living bread that has come down from heaven” (John 5:51).”
Source: Ven. Fulton Sheen, These are the Sacraments