He that knoweth his brother to sin a sin which is not to death, let him ask, and life shall be given to him, who sinneth not to death. There is a sin unto death: for that I say not that any man ask.

“John, too, manifestly teaches the differences of sins, in his larger Epistle, in these words: "If any man see his brother sin a sin that is not unto death, he shall ask, and he shall give him life: for these that sin not unto death," he says. For "there is a sin unto death: I do not say that one is to pray for it. All unrighteousness is sin; and there is a sin not unto death."”

“Touching this difference, we have not only already premised certain antithetical passages of the Scriptures, on one hand retaining, on the other remitting, sins; but John, too, will teach us: "If any knoweth his brother to be sinning a sin not unto death, he shall request, and life shall be given to him; "because he is not "sinning unto death," this will be remissible. "(There) is a sin unto death; not for this do I say that any is to request" -this will be irremissible. For (in making these assertions) he was looking forward to the final clause of his letter, and for that (final clause) he was laying his preliminary bases; intending to say, in the end, more manifestly: "If any knoweth his brother to be sinning a sin not unto death, he shall make request, and the Lord shall give life to him who sinneth not unto death. For there is a sin unto death: not concerning that do I say that one should make request." He, too, (as I have been), was mindful that Jeremiah had been prohibited by God to deprecate (Him) on behalf of a people which was committing mortal sins.”

“That remission cannot in the Church be granted unto him who has sinned against God (i.e., the Holy Ghost): In the Gospel according to Matthew: "Whosoever shall say a word against the Son of man, it shall be forgiven him; but whosoever shall speak against the Holy Ghost, it shall not be forgiven him, neither in this world nor in the world to come." Also according to Mark: "All sins shall be forgiven, and blasphemies, to the sons of men; but whoever shall blaspheme against the Holy Ghost, it shall not be forgiven him, but he shall be guilty of eternal sin." Of this same thing in the first book of Kings: "If a man sin by offending against a man, they shall pray the Lord for him; but if a man sin against God, who shall pray for him?"”

“For it manifestly shows that there are some "brethren" whom we are not commanded to pray for, whereas the Lord bids us pray even for our persecutors. Nor can this question be solved except we acknowledge, that there are some sins in brethren that are worse than the sin of enemies in persecuting. The "sin," therefore, of a brother, "unto death," I suppose to be when, after the acknowledging of God through the grace of our Lord Jesus Christ, one fights against the brotherhood, and is set on by the fire-brands of hatred against the very grace through which he was reconciled to God.”

“If anyone see his brother sin,.... Those who have such an interest at the throne of grace, and such boldness and freedom there, should make use of it for others, as well as themselves, and particularly for fallen believers; for a "brother"; not in a natural or civil sense, but in a spiritual sense, one that is judged to be born again, and belongs to the family and household of God, and is a member of a Gospel church; and so is under the watch, inspection, and care of the saints; and is observed to sin, as the best of men are not without it, nor the commission of it, in thought, word, or deed: and this sin of his is a sin which is not unto death; every sin, even the least sin, is in its own nature mortal, or deserving of death; the proper wages of sin is death, yea, death eternal; yet none of the sins of God's elect are unto death, or issue in death, in fact; which is owing not to any different nature there is in their sins, or to their good works which counterbalance them; but to the grace of God, and to the blood and righteousness of Christ, by which they are pardoned and justified, and freed from obligation to punishment, or eternal death, the just demerits of them: but how should another man know that a brother's sin is not unto death, when it is of the same nature and kind with another man's? it is known by this, that he does not continue in it; he does not live in the constant commission of it; his life is not a course of iniquity; that sin he sins is not a governing one in him; though he falls into it, he rises up out of it through divine grace, and abides not in it; and he has a sense of it, and is sorry for it, after a godly sort, loaths it, and himself for it; is ashamed of it, ingenuously confesses it, and mourns over it and forsakes it: now when any strong believer or spiritual man sees or knows that a brother has sinned, and this is his case, he shall ask; he shall pray to God for him, that he would administer comfort to him, discover his love, and apply his pardoning grace to him, and indulge him with his presence and the light of his countenance: and he shall give him life; that is, God shall give the sinning brother life; by which may be meant comfort, that which will revive his drooping spirits, and cause him to live cheerfully and comfortably, that so he may not be swallowed up with over much sorrow; or he shall grant a discovery of the pardon of his sin unto him, which will be as life from the dead, and will give him a comfortable hope of eternal life, of his right unto it, and meetness for it: for them, or "to them" that sin not unto death, as the Syriac and Arabic versions render it; for this phrase is only descriptive of the persons to whom life is given by God, upon the prayers of saints for them, and not that this life is given to him that prays, and by him to be given to the sinning person. The Vulgate Latin version renders the whole thus, "and life shall be given to him that sins not unto death"; which leaves the words without any difficulty: the Ethiopic version indeed renders it, "and he that prays shall quicken him that sins a sin not unto death"; and this sense some interpreters incline to, and would have with this text compared Ti1 4:16. There is a sin unto death; which is not only deserving of death, as every other sin is, but which certainly and inevitably issues in death in all that commit it, without exception; and that is the sin against the Holy Ghost, which is neither forgiven in this world nor in that to come, and therefore must be unto death; it is a sinning wilfully, not in a practical, but doctrinal way, after a man has received the knowledge of the truth; it is a wilful denial of the truth of the Gospel, particularly that peace, pardon, righteousness, eternal life, and salvation, are by Jesus Christ, contrary to the light of his mind, and this joined with malice and obstinacy; so that there is no more or other sacrifice for such a sin; there is nothing but a fearful looking for of wrath and fury to fall on such opposers of the way of life; and as the presumptuous sinners under Moses's law died without mercy, so must these despiteful ones under the Gospel; see Mat 12:31. Some think there is an allusion to one of the kinds of excommunication among the Jews, called "shammatha", the etymology of which, according to some Jewish writers, is , "there is death" (t). I do not say that he shall pray for it; the apostle does not expressly forbid to pray for the forgiveness of this sin, yet what he says amounts unto it; he gives no encouragement to it, or any hopes of succeeding, but rather the reverse; and indeed where this sin is known, or can be known, it is not to be prayed for, because it is irremissible; but as it is a most difficult point to know when a man has sinned it, the apostle expresses himself with great caution. (t) T. Bab. Moed Katon, fol. 17. 1.”

“A sin which is not unto death….and life shall be given to him. It is hard to determine what St. John here calls a sin which is not unto death, and a sin which is unto death. The difference cannot be the same as betwixt sins that are called venial and mortal; for he says, that if a man pray for his brother who commits a sin that is not unto death, life shall be given to him: therefore such a one had before lost the life of grace, and been guilty of what is commonly called a mortal sin. And when he speaks of a sin that is unto death, and adds these words, I do not say that any one should ask for that sin, it cannot be supposed that St. John would say this of every mortal sin, but only of some heinous sins which are very seldom remitted, because such sinners very seldom repent. By a sin therefore which is not unto death, interpreters commonly understand a wilful apostacy from the faith, and from the known truth, when a sinner hardened by his own ingratitude becomes deaf to all admonitions, will do nothing for himself, but runs on to final impenitence. Nor yet does St. John say that such a sin is never remitted, or cannot be remitted, but only has these words, I do not say that any one should ask for the remission of that sin; that is, though we must pray for all sinners whatsoever, yet man cannot pray for such sinners with such a confidence of obtaining always their petitions, as St. John said before, ver. 14. Whatever exposition we follow on this verse, our faith teaches us from the holy Scriptures, that God desires not the death of any sinner, but that he be converted and live. See Ezechiel xxxiii. 11. Though men’s “sins be as the scarlet, they shall be made as white as snow.” (Isaias i. 18.) It is the will of God that every one come to the knowledge of truth and be saved. See John vi. 40. There is no sin so great but which God is willing to forgive, and has left power in his Church to remit the most enormous sins; so that no sinner need despair of pardon, nor will any sinner perish but by his own fault. (Witham) — A sin unto death. Some understand this of final impenitence, or of dying in mortal sin, which is the only sin that never can be remitted; but, it is probable, he may also comprise under this name the sin of apostacy from the faith, and some other such henious sins as are seldom and hardly remitted: and therefore he gives little encouragement to such as pray for these sinners, to expect what they ask. (Challoner)”

“If any . . . see--on any particular occasion; Greek aorist. his brother--a fellow Christian. sin a sin--in the act of sinning, and continuing in the sin: present. not unto death--provided that it is not unto death. he shall give--The asker shall be the means, by his intercessory prayer, of God giving life to the sinning brother. Kindly reproof ought to accompany his intercessions. Life was in process of being forfeited by the sinning brother when the believer's intercession obtained its restoration. for them--resuming the proviso put forth in the beginning of the verse. "Provided that the sin is not unto death." "Shall give life," I say, to, that is, obtain life "for (in the case of) them that sin not unto death." I do not say that he shall pray for it--The Greek for "pray" means a REQUEST as of one on an equality, or at least on terms of familiarity, with him from whom the favor is sought. "The Christian intercessor for his brethren, John declares, shall not assume the authority which would be implied in making request for a sinner who has sinned the sin unto death (Sa1 15:35; Sa1 16:1; Mar 3:29), that it might be forgiven him" [TRENCH, Greek Synonyms of the New Testament]. Compare Deu 3:26. Greek "ask" implies the humble petition of an inferior; so that our Lord never uses it, but always uses (Greek) "request." Martha, from ignorance, once uses "ask" in His case (Joh 11:22). "Asking" for a brother sinning not unto death, is a humble petition in consonance with God's will. To "request" for a sin unto death [intercede, as it were, authoritatively for it, as though we were more merciful than God] would savor of presumption; prescribing to God in a matter which lies out of the bounds of our brotherly yearning (because one sinning unto death would thereby be demonstrated not to be, nor ever to have been, truly a brother, Jo1 2:19), how He shall inflict and withhold His righteous judgments. Jesus Himself intercedes, not for the world which hardens itself in unbelief, but for those given to Him out of the world.”