Yes, the obviousness of that answer was worth it.  I’m painting a picture here.  Peter obviously matured, and yes, wrote some of the Bible.  1 and 2 Peter are clearly his writings, while Mark is his dictation to John.  Which passage is how we know John Mark matured as a Christian as well?

-2 Timothy 4:11-

-1 John 2:3-

-2 Corinthians 8:9-

-Titus 1:2-