Gregory the Great — as excerpted in the Catena Aurea on Luke 10:3-4

“(Hom. 17. in Ev.) For many when they receive the right of rule, are vehement in persecuting their subjects, and manifesting the terrors of their power. And since they have no bowels of mercy, their desire is to seem to be masters, forgetting altogether that they are fathers, changing an occasion for humility, into an exaltation of power. We must on the other hand consider, that as lambs we are sent among wolves that preserving the feeling of innocence, so we should make no malicious attacks. For he who undertakes the office of preacher ought not to bring evils upon others, but to endure them; who although at times an upright zeal demands that he should deal harshly with his subjects, should still inwardly in his heart love with a fatherly feeling those whom outwardly he visits with censure. And that ruler gives a good example of this, who never submits the neck of his soul to the yoke of earthly desire. Hence it is added, Carry neither purse nor scrip.”