21 Moreover, the Holy Gospel alludes to this when it tells of the many disciples of Christ who turned away and left Our Lord, after hearing Him speak of eating His flesh and drinking His blood. "This is strange talk," they said. "Who can be expected to listen to it" Peter, on the contrary, replied to Jesus' question as to whether the twelve wanted to go away too by promptly and firmly expressing his own faith and that of the other Apostles in these marvelous words: "Lord, to whom should we go? Thy words are the words of eternal life." (8)
Source: Mysterium Fidei (Vatican.va)