Gregory the Dialogist

Then let my shoulder fall from its joining, and mine arm be broken in pieces along with its bones. Because bodily action is carried on by the shoulder and the arm, if the good things which he put forth with the lips he did not fulfil in deed, he wishes to himself 'the shoulder to fall,' and 'the arm to be broken in pieces.' As though he said in plain words, 'If the things that I said I refused to do, this very member of my body, which was given to me for working withal, may I lose, that surely that may fall from the body which I …

Morals on the Book of Job, Book XXI ↗

Thomas Aquinas

It is just that a man should be deprived of the limbs which he uses for injustice, and so he speaks not only of the loss of his hand as a punishment, but also the arm to which the hand is attached, and of the shoulder to which the arm is connected, and so he says, "let my shoulder fall from its joint and let my arm be crushed with its bones," if I have abused my hand by using it to oppress the poor.

Commentary on Job ↗