what does it mean to be Christian ?

[Dogbrain]

• Matthew 16:17-18 17 And Jesus answered him, "Blessed are you, Simon Barjona! For flesh and blood has not revealed this to you, but my Father who is in heaven. And I tell you, you are Peter, and on this rock I will build my church, and the powers of death shall not prevail against it.
• Romans 9:33 as it is written, "Behold, I am laying in Zion a stone that will make men stumble, a rock that will make them fall; and he who believes in him will not be put to shame."
• Matthew 21:42 Jesus said to them, "Have you never read in the scriptures: `The very stone which the builders rejected has become the head of the corner; this was the Lord's doing, and it is marvelous in our eyes'?

"This rock" refers to Peter's faith, not Peter the man. If the "stone that will make men stumble" is a specific man, then it would have to be St. James, who was the first Bishop of Jerusalem. St. Peter served in Antioch and in Rome, neither of which are "in Zion". Finally, "stone" to which Christ was referring was the Messiah, not one of the first Patriarchs.