George Leo Haydock

In him: i.e. in this word, or Son of God, was life; because he gives life to every living creature. Or, as Maldonatus expounds it, because he is the author of grace, which is the spiritual life of our souls. — And the life was the light of men, whether we expound it of a rational soul and understanding, which he gives to all men; or of the spiritual life, and those lights of graces, which he gives to Christians. (Witham)