Matthew 16:17

Βὰρ Ἰωνᾶ, ‘son of Jonah,’ or ‘son of John.’ The Greek form may stand for either name (see Bp. Lightfoot on a Fresh Revision of N.T., pp. 159, 160); but the reading adopted by the best editors John 1:43, υἱὸς Ἰωάνου, seems conclusive in favour of the latter rendering. Bar is Aramaic for son; cp. Bar-abbas, Bar-tholomew, Bar-nabas.

ὅτι σὰρξ καὶ αἷμα κ.τ.λ. Not man, but God; ‘flesh and blood’ was a common Hebrew expression in this contrast. The recognition was not by material test or human judgment, but by the witness of the Holy Spirit.