Transubstantiation reflects Catholic faith in the literalness
of the words of the Bible. Jesus (omnipotent God)
said:
"This is my body; this is my blood." And again Jesus said:
"I am the bread of life;" "My flesh
is true food; my blood is true drink;" "He who eats my flesh and drinks my blood ...;"
etc.
Catholics take Jesus at His word: the bread is his
body;
the wine is his blood.
From the Apostles at the Last Supper until today,
the bread
and wine of Eucharist looks and feels and tastes
like bread
and wine in the eating and drinking.
Similar to all of God's Word, faith is essential. Faith in what?
in the words of Jesus even though the bread does not
look,
feel, taste like flesh; even though the wine does
not look, feel,
taste like blood.