Gregory the Great
Catena Aurea · Matthäusevangelium 10
He that receiveth you receiveth me, and he that receiveth me receiveth him that sent me. He that receiveth a prophet in the name of a prophet shall receive a prophet’s reward; and he that receiveth a righteous man in the name of a righteous man shall receive a righteous man’s reward. And whosoever shall give to drink unto one of these little ones a cup of cold water only in the name of a disciple, verily I say unto you, he shall in no wise lose his reward.
(Hom. in Ev. xx. 12.) He says not, a reward from a prophet, or righteous man, but the reward of a prophet or righteous man. For the prophet is perhaps a righteous man, and the less he possesses in this world, the greater confidence has he in speaking in behalf of righteousness. He who hath of this world’s goods, in supporting such a man, makes himself a free partaker in his righteousness, and shall receive the reward of righteousness together with him whom he has aided by supporting him. He is full of the spirit of prophecy, but he lacks bodily sustenance, and if the body be not supported, it is certain that the voice will fail. Whoso then gives a prophet food, gives him strength for speaking, therefore together with the prophet he shall receive the prophet’s reward, when he shews before the face of God what bounty he shewed him.