Matthew 16:16

Simon Peter answering. As Simon Peter had been constituted the first in the college of apostles, (Matthew x. 2.) and therefore surpasseth the others in dignity as much as in zeal, without hesitation, and in the name of all, he answers: thou art the Christ, the Redeemer promised to the world, not a mere man, not a mere prophet like other prophets, but the true and natural Son of the living God. Thus Sts. Chrysostom, Cyril, Ambrose, Augustine, and Tirinus. When our Saviour inquired the opinion of him, Peter, as the mouth of the rest, and head of the whole college, steps forth, and prevents the others. (St. John Chrysostom, hom. lv.) --- Tu es Christus, filius Dei vivi; or, as it is in the Greek, o christos, o vios; The Christ, the Son, the Christ formerly promised by the law and the prophets, expected and desired by all the saints, the anointed and consecrated to God: Greek: o vios, the Son, not by grace only, or an adoptive filiation like prophets, to whom Christ is here opposed, but by natural filiation, and in a manner that distinguishes him from all created beings. --- Thou art [1] Christ, the Son of the living God, not by grace only, or by adoption, as saints are the sons of God, but by nature, and from all eternity, the true Son of the living God. (Witham)

[BIBLIOGRAPHY]

Tu es Christus, Filius Dei vivi. Greek: o christos o vios tou theou. Where the Greek articles seem significant.