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

“(Hom. 17. in Ev.) For the preacher (of the Gospel) ought to have such trust in God, that although he has provided not for the expenses of this present life, he should still be most certainly convinced that these will not fail him; lest while his mind is engaged in His temporal things, he should be less careful for the spiritual things of others.”