John 14:27

27.Peace I leave with you. By the wordpeace he means prosperity, which men are wont to wish for each other when they meet or part; for such is the import of the word peace in the Hebrew language. He therefore alludes to the ordinary custom of his nation; as if he had said, I give you my Farewell But he immediately adds, that this peace is of far greater value than that which is usually to be found among men, who generally have the word peace but coldly in their mouth, by way of ceremony, or, if they sincerely wish peace for any one, yet cannot actually bestow it. But Christ reminds them that his peace does not consist in an empty and unavailing wish, but is accompanied by the effect. In short, he says that he goes away from them in body, but that his peace remains with the disciples; that is, that they will be always happy through his blessing.

Let not your heart be troubled. He again corrects the alarm which the disciples had felt on account of his departure. It is no ground for alarm, he tells them; for they want only his bodily presence, but will enjoy his actual presence through the Spirit. Let us learn to be always satisfied with this kind of presence, and let us not give a loose reign to the flesh, which always binds God by its outward inventions.