In the book, “The Essential Catholic Survival Guide”, they use Matthew 18:21 to defend how St. Peter spoke for the apostles.
Matthew 18:21 -
Then Peter approaching asked him, “Lord, if my brother sins against me, how often must I forgive him? As many as seven times?”
How does this verse defend that St. Peter was the one who spoke for the apostles?
You can read it in context here: