1 John 3:7-10

Verse 7

Let no man deceive you - Either by asserting that "you cannot be saved from sin in this life," or "that sin will do you no harm and cannot alter your state, if you are adopted into the family of God; for sin cannot annul this adoption." Hear God, ye deceivers! He that doeth righteousness is righteous, according to his state, nature, and the extent of his moral powers.

Even as he is righteous - Allowing for the disparity that must necessarily exist between that which is bounded, and that which is without limits. As God, in the infinitude of his nature, is righteous; so they, being filled with him, are in their limited nature righteous.
Verse 8

He that committeth sin is of the devil - Hear this, also, ye who plead for Baal, and cannot bear the thought of that doctrine that states believers are to be saved from all sin in this life! He who committeth sin is a child of the devil, and shows that he has still the nature of the devil in him; for the devil sinneth from the beginning - he was the father of sin, brought sin into the world, and maintains sin in the world by living in the hearts of his own children, and thus leading them to transgression; and persuading others that they cannot be saved from their sins in this life, that he may secure a continual residence in their heart. He knows that if he has a place there throughout life, he will probably have it at death; and, if so, throughout eternity.

For this purpose - Εις τουτο· For this very end - with this very design, was Jesus manifested in the flesh, that he might destroy, ἱνα λυσῃ, that he might loose, the bonds of sin, and dissolve the power, influence, and connection of sin. See on 1Jn 3:3 (note).
Verse 9

Whosoever is born of God - Γεγεννημενος, Begotten of God, doth not commit sin: "that is," say some, "as he used to do, he does not sin habitually as he formerly did." This is bringing the influence and privileges of the heavenly birth very low indeed. We have the most indubitable evidence that many of the heathen philosophers had acquired, by mental discipline and cultivation, an entire ascendency over all their wonted vicious habits. Perhaps my reader will recollect the story of the physiognomist, who, coming into the place where Socrates was delivering a lecture, his pupils, wishing to put the principles of the man's science to proof, desired him to examine the face of their master, and say what his moral character was. After a full contemplation of the philosopher's visage, he pronounced him "the most gluttonous, drunken, brutal, and libidinous old man that he had ever met." As the character of Socrates was the reverse of all this, his disciples began to insult the physiognomist. Socrates interfered, and said, "The principles of his science may he very correct, for such I was, but I have conquered it by my philosophy." O ye Christian divines! ye real or pretended Gospel ministers! will ye allow the influence of the grace of Christ a sway not even so extensive as that of the philosophy of a heathen who never heard of the true God?
Verse 10

In this the children of God are manifest - Here is a fearful text. Who is a child of the devil? He that commits sin. Who is a child of God? He that works righteousness. By this text we shall stand or fall before God, whatever our particular creed may say to the contrary.

Neither he that loveth not his brother - No man is of God who is not ready on all emergencies to do any act of kindness for the comfort, relief, and support of any human being. For, as God made of one blood an the nations of men to dwell upon the face of the whole earth, so all are of one family; and consequently all are brethren, and should love as brethren.
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