1) if the woman was actually caught in adultery, they were to bring her to the high priest, not a prophet
2) the Law of God says that they are to bring both, the man & woman caught in adultery, but they only brought the woman
3) they were to bring two eye witnesses and they brought none
So since they did not bring the man, and they brought no witnesses, and most important, they did not bring their accusations to the high priest, they brought false testimony and that is what I believe Christ wrote in the sand...
Deu 19:18 And the judges shall diligently search and see if the witness is a false witness, who has falsely accused his brother, 19 then you shall do to him as he thought to have done to his brother. Thus you shall purge the evil from your midst. 20 And let the rest hear and fear, and never again do this evil matter in your midst.
That’s a great perspective. Thanks for the quote.
Notice however that the content of the writing is not disclosed. Therefore it remains a matter of our opinion what it might have been. That wasn’t important; what was important was that the “loophole” in the Mosaic law was used to the goal of mercy.