Not as Cain, who was of that wicked one, and slew his brother. And wherefore slew he him? Because his own works were evil, and his brother's righteous.

Not as Cain, who was of the wicked one, and killed his brother. And wherefore did he kill him? Because his own works were wicked: and his brother's just.

not as Cain was of the wicked one, and slew his brother; and on account of what slew he him? because his works were wicked, and those of his brother righteous.

Not as Cain, who was of that wicked one, and slew his brother. And why did he slay him? Because his own works were evil, and his brother's righteous.

not as Cain, of the evil one he was, and he did slay his brother, and wherefore did he slay him? because his works were evil, and those of his brother righteous.

We are not to resemble Cain, who was a child of the Evil one and killed his own brother. And why did he kill him? Because his own actions were wicked and his brother's actions righteous.

Not being of the Evil One like Cain, who put his brother to death. And why did he put him to death? Because his works were evil and his brother's works were good.

Do not be like Cain, who was of the evil one, and who killed his brother. And why did he kill him? Because his own works were wicked, but his brother's works were just.

We must not be like Cain, who belonged to the evil one and murdered his brother. Why did he kill him? Because his actions were evil, and his brother's were righteous.

Not as Cain This is another confirmation, taken from what is contrary; for in the reprobate and the children of the devil hatred reigns, and it holds, as it were, the chief place in their life; and he brings forward Cain as an instance. It served in the meantime to give them consolation, as he at length concluded by saying, Marvel not, if the world hate you. This explanation ought to be carefully noticed, for men ever blunder as to the way of living, because they make holiness to consist of fictitious works, and while they torment themselves with trifles, they think themselves doubly acceptable to God, as the monks, who proudly call their mode of living a state of perfection; nor is there any other worship of God under the Papacy but a mass of superstitions. But the Apostle testifies that this righteousness alone is approved by God, that is, if we love one another; and further, that the devil reigns where hatred, dissimulation, envy, and enmity prevail. We ought, however, at the same time, to bear in mind what I have already touched upon, that brotherly love, as it proceeds from the love of God as an effect from a cause, is not disjoined from it, but on the contrary is commended by John on this account, because it is an evidence of our love to God. By saying that Cain was driven to slay his brother, because his works were evil, he intimates what I have already stated, that when impiety rules, hatred occupies the first place. He refers to Abel's righteous works, that we may learn to endure patiently when the world hates us gratuitously, without any just provocation.

Not as Cain - Not manifesting the spirit which Cain did. His was a most remarkable and striking instance of a want of love to a brother, and the case was well adapted to illustrate the propriety of the duty which the apostle is enjoining. See Genesis 4:4-8.
Who was of that wicked one - Of the devil; that is, he was under his influence, and acted from his instigation.
And wherefore slew he him? - Because his own works were evil, and his brother's righteous." He acted under the influence of envy. He was dissatisfied that his own offering was not accepted, and that his brother's was. The apostle seems desirous to guard those to whom he wrote against the indulgence of any feelings that were the opposite of love; from anything like envy toward more highly favored brethren, by showing to what this would lead if fairly acted out, as in the case of Cain. A large part of the crimes of the earth have been caused, as in the murder of Abel, by the want of brotherly love. Nothing but love would be necessary to put an end to the crimes, and consequently to a large part of the misery, of the world.

Not as Cain - Men should not act to each other as Cain did to his brother Abel. He murdered him because he was better than himself. But who was Cain? Εκ του πονηρου ην, he was of the devil. And who are they who, through pride, lust of power, ambition, gain, etc., murder each other in wars and political contentions? Εκ του πονηρου εισι. To attempt to justify the principle, and excuse the instigators, authors, abettors, etc., of such wars, is as vain as it is wicked. They are opposed to the nature of God, and to that message which he has sent to man from the beginning: Love one another. Love your enemies. Surely this does not mean, Blow out their brains, or, Cut their throats. O, how much of the spirit, temper, and letter of the Gospel have the nations of the world, and particularly the nations of Europe, to learn!
And wherefore slew he him? - What could induce a brother to imbrue his hands in a brother's blood? Why, his brother was righteous, and he was wicked; and the seed of the wicked one which was in him induced him to destroy his brother, because the seed of God - the Divine nature, was found in him.

(12) Not as Cain, [who] was of that wicked one, and slew his brother. (13) And wherefore slew he him? Because his own works were evil, and his brother's righteous.
(12) An amplification taken from the contrary example of Cain who slew his brother.
(13) A short digression: Let us not marvel that we are hated by the world for doing our duty, for such was the condition of Abel who was a just person: and who would not rather be like him than Cain?

Not as Cain,.... That is, let us not be like him, or do as he did, hate the brethren. The apostle illustrates brotherly love by its contrary, in the instance of Cain, who was the first instance and example of hatred of the brethren, and of fratricide, and a very detestable one, by which he would dissuade from so vile and abominable a practice:
who was of that wicked one; Satan, a child of his, an imitator of him, one that appeared to be under his influence, and to belong unto him. So the Jews say of Cain (n), that
"he was of the side of the serpent (the old serpent the devil); and as the way of the serpent is to slay and to kill, so Cain immediately became a murderer.''
And again,
"because Cain came from the side of the angel of death, he slew his brother (o);''
though they say that he afterwards repented, and became worthy of paradise (p).
And slew his brother; see Genesis 4:8. According to the tradition of the Jews (q) he struck a stone into his forehead, and killed him:
and wherefore slew he him? what was the cause and occasion of it? what moved him to it?
because his own works were evil, and his brother's righteous; or "his work", as the Ethiopic version reads: the sacrifice which he offered up, which, though it was not evil as to the matter and substance of it, yet was so, being offered with an evil mind, and with an hypocritical heart, and without faith in the sacrifice of Christ, and so was unacceptable to God; whereas, on the other hand, the sacrifice his brother brought was offered up in the faith of Christ, by which he obtained a testimony that he was righteous, and that the work he did was a righteous work, being done in faith, and so was acceptable to God; which Cain perceiving, was filled with envy, and this put him upon killing him. The Jews (r) relate the occasion of it after this manner;
"Cain said to Abel his brother, come, and let us go out into the open field; and when they were both out in the open field, Cain answered and said to Abel his brother, there is no judgment, nor Judge, nor another world; neither will a good reward be given to the righteous, nor vengeance be taken on the wicked; neither was the world created in mercy, nor is it governed in mercy; or why is thy offering kindly accepted, and mine is not kindly accepted? Abel answered and said to Cain, there is judgment, and there is a Judge, and there is another world; and there are gifts of a good reward to the righteous, and vengeance will be taken on the wicked; and the world was created in mercy, and in mercy it is governed, for according to the fruit of good works it is governed; because that my works are better than thine, my offering is kindly accepted, and thine is not kindly accepted; and they both strove together in the field, and Cain rose up against Abel his brother, and slew him.''
In the Hebrew text in Genesis 4:8; there is an extraordinary large pause, as if a discourse of this kind, which passeth between the two brothers, was to be inserted. Philo the Jew says (s), that in the contention or dispute between Cain and Abel, Abel attributed all things to God, and Cain ascribed everything to himself; so that the controversy was about grace and works, as now; and as then Cain hated his brother upon this account, so now carnal men hate and persecute the saints, because they will not allow their works to be the cause of justification and salvation: and from hence also it may be observed, that a work may be, as to the matter of it, good, and yet as to its circumstances, and the end and view of it, evil.
(n) Midrash Ruth in Zohar in Genesis. fol. 42. 4. (o) Zohar in ib. fol. 43. 1. (p) Ib. fol. 41. 1, 2. (q) Targum Jonah. in Genesis. iv. 8. Pirke Eliezer, c. 21. (r) Targum Hieros. & Jonah. in Genesis. iv. 8. (s) Quod Det. Potior. p. 161.

who--not in the Greek.
of that wicked one--Translate, "evil one," to accord with "Because his own works were evil." Compare 1-John 3:8, "of the devil," in contrast to "of God," 1-John 3:10.
slew he him? Because his own works were evil, and his brother's righteous--through envy and hatred of his brother's piety, owing to which God accepted Abel's, but rejected Cain's offering. Enmity from the first existed between the seed of the woman and the seed of the serpent.

Who was of the wicked one - Who showed he was a child of the devil by killing his brother. And wherefore slew he him - For any fault? No, but just the reverse; for his goodness.