Jesus calls himself the good shepherd. What kind of claim is this? How does he reflect an earthly shepherd and how does he surpass that to be something greater by the same name?

Image: The Parable of the Good Shepherd, Pieter Brueghel the Elder, Public Domain. Image location: https://commons.wikimedia.org/wiki/File:The_Parable_of_the_Good_Shepherd_MET_DP818250.jpg