He answered one of them. The Lord condescended to show, not to all the labourers, but to one of them—the ringleader probably—the futility of the ground of his murmur. Christ often explains himself to his friends, while he refuses further elucidation to enemies and the hardened.
Friend ( ἑταῖρε). Not a term of affection, or special good will, but one of indifference, addressed to an inferior. It was the word used to Judas (Matthew 26:50) when he came to betray his Lord, "Friend, wherefore art thou come?"
I do thee no wrong. The labourer had really nothing to complain of in strict justice; he had received the full amount of the stipulated wages. But he very naturally felt that he had not been fairly dealt with.
He would say to himself, "If one hour's work, and that in the cool of the evening, is deemed worth a penny, surely a whole day's labour, in the full heat of the sun, ought to deserve a higher remuneration."
The difficulty here must be felt by every one. Nor is the master's solution perfect; it would scarcely commend itself to the dissatisfied murmurer. And doubtless it is not intended to be complete.