John Calvin on 1 Corinthians 12:21-22

21. And the eye cannot say to the hand Hitherto he has been showing, what is the office of the less honorable members — to discharge their duty to the body, and not envy the more distinguished members. Now, on the other hand, he enjoins it upon the more honorable members, not to despise the inferior members, which they cannot dispense with. The eye excels the hand, and yet cannot despise it, or insult over it, as though it were useless; and he draws an argument from utility, to show that it ought to be thus — “Those members, that are less esteemed, are the more necessary: hence, with a view to the safety of the body, they must not be despised.” He makes use of the term weaker here, to mean despised, as in another passage, when he says that he glories in his infirmities, (2 Corinthians 12:9,) he expresses, under this term, those things which rendered him contemptible and abject.