One major point in last Sunday's Gospel is Jesus renaming of Simon as Peter, and how his life will radically change because of it. That Gospel had another major point, Simon Peter's recognition of who Jesus is - "You are the Christ, the son of the living God."
We've heard the word "Christ" so many times, it almost turns into Jesus' last name in our ears. Hearing it the way Simon Peter says it helps us see what it really is - a description that literally means "anointed." Meaning that Simon Peter understands Jesus to be the anointed one, the Messiah (and the son of God).
So why bring up all of this stuff from last week?
Because the readings for this Sunday pair with the readings for last Sunday, so much so that this Sunday's Gospel is actually the back half of last Sunday's Gospel.
We'll look at this Sunday's readings tomorrow.
Sunday's Readings: http://www.usccb.org/bible/readings/083114.cfm