Do You Love Me?
Since it is difficult to see any consistent distinctions that John intended, most scholars see these as stylistic variations.
There can be little doubt but that the whole scene is meant to show us Peter as completely restored to his position of leadership. He has three times denied his Lord. Now he has three times affirmed his love for Him, and three times he has been commissioned to care for the flock. This must have had the effect on the others of a demonstration that, whatever had been the mistakes of the past, Jesus was restoring Peter to a place of trust. It is further worth noting that the one thing about which Jesus questions Peter prior to commissioning him to tend the flock is love. This is the basic qualification for Christian service (Morris, p. 875).
Peter lived 3 decades serving the Lord and anticipating the death that was before him (2 Pet. 1:12–15), but he wrote that such suffering and death for the Lord brings praise to God (1 Pet. 4:14–16). Church tradition records that Peter suffered martyrdom under Nero (ca. A.D. 67–68), being crucified upside down, because he refused to be crucified like his Lord.