15. Looking diligently, or, taking care, or, attentively providing, etc. (256) By these words he intimates that it is easy to fall away from the grace of God; for it is not without reason that attention is required, because as soon as Satan sees us secure or remiss, he instantly circumvents us. We have, in short, need of striving and vigilance, if we would persevere in the grace of God.
Moreover, under the word grace, he includes our whole vocation. If any one hence infers that the grace of God is not efficacious, except we of our own selves cooperate with it, the argument is frivolous. We know how great is the slothfulness of our flesh; it therefore wants continual incentives; but when the Lord stimulates us by warning and exhortation, he at the same time moves and stirs up our hearts, that his exhortations may not be in vain, or pass away without effect. Then from precepts and exhortations we are not to infer what man can do of himself, or what is the power of freewill; for doubtless the attention or diligence which the Apostle requires here is the gift of God.
Lest any root, etc. I doubt not but that he refers to a passage written by Moses in Deuteronomy 29:18; for after having promulgated the Law, Moses exhorted the people to beware, lest any root germinating should bear gall and wormwood among them. He afterwards explained what he meant, that is, lest any one, felicitating himself in sin, and like the drunken who are wont to excite thirst, stimulating sinful desires, should bring on a contempt of God through the alluring of hope of impunity. The same is what the Apostle speaks of now; for he foretells what will take place, that is, if we suffer such a root to grow, it will corrupt and defile many; he not only bids every one to irradiate such a pest from their hearts, but he also forbids them to allow it to grow among them. It cannot be indeed but that these roots will ever be found in the Church, for hypocrites and the ungodly are always mixed with the good; but when they spring up they ought to be cut down, lest by growing they should choke the good seed.
He mentions bitterness for what Moses calls gall and wormwood; but both meant to express a root that is poisonous and deadly. Since then it is so fatal an evil, with more earnest effort it behooves us to check it, lest it should rise and creep farther. (257)
(256) It means properly overseeing and is rendered “taking the oversight,” in 1 Peter 5:2, where alone it occurs elsewhere. The word bishop comes from it. It is rendered, “taking heed,” by Erasmus; “Diligently attending,” by Grotius; “Taking care,” by Beza; “Looking to it,” by Doddridge; “carefully observing,” by Macknight; and “Seeing to it.” By Stuart. Considering what follows, “Taking heed” would be the best version. — Ed.
(257) See Appendix U 2.