The Great Exchange
"For Christ also suffered once for sins, the righteous for the unrighteous, to bring you to God." (1 Peter 3:18 NIV)
Once was enough!
Notice that this promise says that Christ suffered "once for sins". Two thousand years ago He completely took care of sin once and for all with one great act of pesonal sacrifice! He went to the cross and shed His blood. He will never need to do it again because once was enough to do what was needed! This is known as the "great exchange!" Christ suffered for sins, but not for His own sins (He was completely righteous!). But He suffered for our sins (we were completely unrighteous!) in order to bring us to God!