Interesting!
I did some reading. This story apparently had also been placed in the Book of Luke at one time.
It seems the Church Fathers or scribes had no problem excluding or including portions that suit their purpose. Pieces to a puzzle.
I find the story itself interesting.
The story states the woman was brought before Jesus to trap him.
As I understand it the Churches who used the story used it to show forgiveness.
Could the story be an actual representation?
The Law of Moses says to stone such women, but there is also the test of the bitter water (Numbers 5:20-31), which doesn't seem to end in death (unless the water got you). This was for suspicion of adultery.
Even Jesus said in Matthew 19:9 not to divorce except for immorality. If the wife was to be stoned, then there would have been no need to divorce.
Of course you would think that people committing adultery would be somewhat discrete so as not to have two witnesses.
Since they were standing in the temple courts, the Pharisees would not have stoned the woman right there anyway, neither could Jesus. Have you read the rules for stoning?
Excerpt from
Babylonian Talmud
MISHNA IV.: The stoning-place was two heights of a man. One of the witnesses pushed him on his thighs (that he should fall with the back to the surface), but if he fell face down, he had to be turned over. If he died from the effects of the first fall, nothing more was to be done. If not, the second witness took a stone and thrust it against his heart. If he died, nothing more was to be done; but if not, all who were standing by had to throw stones on him. Thus [Deut. xvii. 7]: "The hand of the witnesses shall be first upon him, to put him to death, and the hand of all the people at the last."
Let's say the Pharisees did bring a woman who had not been charged yet to Jesus and claimed she was caught in the act of adultery. Now if Jesus answers that she should not be stoned, would he truly have broken any law?
Now if the woman truly was caught in the act of adultery, the Pharisees should have brought her before the Sanhedrin for judgement no matter what Jesus said. They themselves let her go.
Just throwing this out for discussion if you wish.
A gentle answer turns away wrath, But a harsh word stirs up anger.