this may help
"Neither do I condemn thee; go, and sin no more"
. Consider this,
(a.) As her discharge from the temporal punishment: "If they do not condemn thee to be stoned to death, neither do I.’’ Not that Christ came to disarm the magistrate of his sword of justice, nor that it is his will that capital punishments should not be inflicted on malefactors; so far from this, the administration of public justice is established by the gospel, and made subservient to Christ’s kingdom: By me kings reign. But Christ would not condemn this woman, (a.) Because it was none of his business; he was no judge nor divider, and therefore would not intermeddle in secular affairs. His kingdom was not of this world. Tractent fabrilia fabri—Let every one act in his own province. (b.) Because she was prosecuted by those that were more guilty than she and could not for shame insist upon their demand of justice against her. The law appointed the hands of the witnesses to be first upon the criminal, and afterwards the hands of all the people, so that if they fly off, and do not condemn her, the prosecution drops. The justice of God, in inflicting temporal judgments, sometimes takes notice of a comparative righteousness, and spares those who are otherwise obnoxious when the punishing of them would gratify those that are worse than they, Deu. 32:26, 27. But, when Christ dismissed her, it was with this caution, Go, and sin no more. Impunity emboldens malefactors, and therefore those who are guilty, and yet have found means to escape the edge of the law, need to double their watch, lest Satan get advantage; for the fairer the escape was, the fairer the warning was to go and sin no more. Those who help to save the life of a criminal should, as Christ here, help to save the soul with this caution.
(b.) As her discharge from the eternal punishment. For Christ to say, I do not condemn thee is, in effect, to say, I do forgive thee; and the Son of man had power on earth to forgive sins, and could upon good grounds give this absolution; for as he knew the hardness and impenitent hearts of the prosecutors, and therefore said that which would confound them, so he knew the tenderness and sincere repentance of the prisoner, and therefore said that which would comfort her, as he did to that woman who was a sinner, such a sinner as this, who was likewise looked upon with disdain by a Pharisee (Lu. 7:48, 50): Thy sins are forgiven thee, go in peace. So here, Neither do I condemn thee. Note, (a.) Those are truly happy whom Christ doth not condemn, for his discharge is a sufficient answer to all other challenges; they are all coram non judice—before an unauthorized judge. (b.) Christ will not condemn those who, though they have sinned, will go and sin no more, Ps. 85:8; Isa. 55:7. he will not take the advantage he has against us for our former rebellions, if we will but lay down our arms and return to our allegiance. (c.) Christ’s favour to us in the remission of the sins that are past should be a prevailing argument with us to go and sin no more, Rom. 6:1, 2. Will not Christ condemn thee? Go then and sin no more.
this is the commentary by Matthw Henry on the whole event.....