Gregory the Great

(Hom. in Evang. xiv.) Some there are who love earthly possessions more than the sheep, and do not deserve the name of a shepherd. He who feeds the Lord’s flock for the sake of temporal hire, and not for love, is an hireling, not a shepherd. An hireling is he who holds the place of shepherd, but seeketh not the gain of souls, who panteth after the good things of earth, and rejoices in the pride of station.