Contemporary English Version (CEV)
It's easier when one person takes the fall, when they assume the blame that should rightfully be spread upon the entire group. The blame falls harder on that one person, but the others are then free.
What happens, then, is that the others who deserve the blame often forget their culpability. They deny that they were guilty, even as the guilt eats away at them. They shape their lives to isolate the memory of pain, and it erodes part of us.
I believe that sin is still real, and that it has power over us. When we forget that we are guilty, because Jesus took the full punishment of our sins, we shape our lives to avoid mention of sin. We don't like thinking about it, so we ignore it, but it eats away at us. We forget to be grateful for the freedom Christ has given us, and instead we become imprisoned to other lessor gods who promise us freedom at a lower price, albeit a freedom that often rings hollow after time.
Peter's denial is complicated, driven by fear, unaware of the events circulating in the air that will take place in the coming days. He reacts impulsively, and impulse leads us to protect our own skin.
So let us not shrink back in culpability. May we accept our sin and our role, and may we embrace the freedom that Christ gives us. We must go through the cross to get there, but the light that shines on the other side is worth enduring the pain.