Charles Ellicott Commentary Matthew 10:42

"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 10:42 (ASV)

One of these little ones — This term was commonly used for the disciples of a Rabbi. Our Lord, as the great Master sending out His disciples, uses the term in this sense. He would not disregard even a cup of cold water given to the humblest disciple simply because they are a disciple and for Christ’s sake.

On its own, this statement does not go beyond this specific meaning. However, the language of Matthew 25:40 justifies extending this principle to every act of kindness done to anyone. This kindness is done in the name of the humanity He shares with those whom He is not ashamed to call His brethren (Hebrews 2:11).