Matthew 10:42 in the King James Version
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.
Context
41 He who receives a prophet in the name of a prophet will receive a prophet’s reward. He who receives a righteous man in the name of a righteous man will receive a righteous man’s reward.
42 Whoever gives one of these little ones just a cup of cold water to drink in the name of a disciple, most certainly I tell you, he will in no way lose his reward.”