What is the meaning of Matthew 10:40-42?

40 He that receiveth you receiveth me, and he that receiveth me receiveth him that sent me. 41 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. 42 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. (Matthew 10:40-42 KJV)

William Burkitt’s Commentary

Here in the close of the chapter, our blessed Saviour encourages his apostles to faithfulness in their office, by assuring them that he should reckon and esteem all the kindness shown to them as done unto himself: and to encourage the world to be kind to his disciples and ministers, he assures them that even a cup of cold water should meet with a liberal reward. How cold is their charity who deny a cup of cold water to the ministers and disciples of Christ!

Learn, 1. That there is some special and eminent reward due to the faithful prophets of God above other men.

2. That he that shall entertain a prophet and do any good office for him, under that name, that is, for his office sake, shall be partaker of that reward.

3. That the least office of love and respect, of kindness and charity, which we show to any of the ministers or members of Jesus Christ for his sake, Christ accounts it as done unto himself, and it shall be rewarded by himself.