When a rich ruler asks Jesus what more he needs to do, Jesus gives him an impossible challenge: to let go of all that belongs to him, and to follow Jesus. The challenge is meant to show him his real problem is with his heart. It's a problem that is impossible to solve without God - and yet God changes hearts of stone for hearts of flesh, bringing new life. Peter knows what it's like to leave everything and follow Jesus - and Jesus reassures him that we can never find ourselves worse off because of leaving something behind to follow Him.
