Briefly, the Pharisees -- the ones always trying to trip up Jesus, who had said he had not come to abolish the law and the prophets -- brought an adulteress to Jesus while he was at the temple teaching the people. They said, "Teacher, this woman was caught in the act of adultery. In the Law Moses commanded us to stone such women. Now what do you say?" (John 8:4-5) In answer, Jesus did a most remarkable thing, he said nothing. Instead he bent down and wrote on the ground with his finger.
What was he writing?
The Bible does not tell us. Some hypothesize he was writing down the sins of all the people there. Some that he was writing out the law or names of people she had wronged. I wonder if he was writing down the woman's life history, from the time she was born to the present day, detailing all that had happened to her to skew her sense of right and wrong or deprive her of a sense of worth and self-preservation. I wonder if he was writing down all the poor choices she had made that led to the moment of the Pharisees capturing her in the middle of commiting adultery.
What was the purpose of writing in the sand?
If it was her life history or all their sins, then he was both detailing it and making it temporary. With one stroke, all that he had written could be erased, just like with one merciful word, all her choices, all her history that she'd like to forget or all their sins, would be as if it had never happened.
Finally Jesus answers the peoples' persistent questions: "If any one of you is without sin, let him be the first to throw a stone at her." (John 8:7)
Since no-one is without sin, they all left one by one. The older ones first. Interesting that. The older you get, the more honest you become with yourself, the more you see yourself clearly and uncompromisingly, without excuse or rationalization. Probably too, the older you are the easier it is to live by the Sermon on the Mount, where Jesus teaches us how to think good thoughts (a Zoroastrian concept) so as to reach for a life without sin. The Sermon on the Mount is all about self-awareness and self-analysis of one's thoughts so as to resist bad thoughts and aim for good thoughts. Here, in John 8:3-11, he is challenging the people and the Pharisees to analyse themselves.
The last part of this story is the one people use to justify moral relativism, while ignoring the very last few words that make it clear that Jesus did not accept her sin even though he did not condemn her (notice the distinction).
Jesus straightened up and asked her, "Woman, where are they? Has no one condemned you?"
"No one, sir," she said.
"Then neither do I condemn you," Jesus declared. "Go now and leave your life of sin." John 8:10-11, bolding mine)
Jesus wrote something in the ground that led him to challenge those who would stone her, to do so only if they were sinless and then, when all had left, to not condemn her. It is said that Jesus was sinless. Yet he did not do what he had challenged the others to do if sinless: throw stones at her.
People rush to judge others and condemn them, not with stones, but with words, actions, and isolation. They do not forget, not even after remorse is expressed, and hold the person hostage to past trangressions or thoughtless actions. When given a chance, they avenge themselves. I remember listening to the critics of Dr. Laura. She would often say, "when you know better, you do better," meaning that sometimes people do the wrong thing not because they're bad but because they didn't know better. Once they know better, they change. And in that case, you forget about it; the it being the past bad behaviour. Her critics would do the opposite. Critics of politicians also rush to haul out old bad deeds and wave them around to anyone who will listen and join them in condemnation. One needs to lead a sinless life, otherwise someone, somewhere, in the grip of envy and covetousness (against Commandment #10), will bring up past trangressions as proof of a person's unfitness to lead a life. In their eyes, the sin remains.
On a personal level, like the Pharisees did here, people gang up in packs, like ravaging wolves, to attack the sinner. Too often, instead of having a calm conversation one on one about how the "sinner" hurt them until the "sinner" gets it, the victim talks with others, gathering support and steam, until feeling safe as one of many, they surround and attack the unsuspecting person. (Sometimes this happens even after the sin is pointed out one-on-one or with a compassionate third party, remorse is expressed, and reconciliation happens.)
What is the motive then?
The motive for the Pharisees was to catch Jesus out so as to be able to arrest him and, as well, to show their righteousness by using Moses' law against this more obvious sinner. The motive for people who do it today is less obvious, to me anyway. But Jesus says to them, as he did in the Bible, do not condemn, for I do not condemn.
There is one more thing he says to the oppressor, the one who sinned: "Do not sin again."
These last words are a direct contradiction to those who use this passage to espouse moral relativism. Jesus did not approve of what she had done, else why tell her not to sin again? In John 5:14, Jesus said to a 38-year-long sick man he made well, "See, you have been made well! Do not sin any more, so that nothing worse happens to you." (from NRSV) I'm going to leave that can of worms opened up by the last phrase for now. The important thing is that he tells someone who was a victim of illness not to sin also. This man is not the obvious sinner the adulteress was, so why tell him not to sin? Jesus calls all of us not to sin, and he lays out how to strive for that pinnacle in the Sermon on the Mount.
Clearly though, in each of these cases -- the adulteress and the ill man -- he never condemned the person. Instead he showed compassion towards the person, curing one, releasing the other. He showed mercy to the souls that God created. Yet he abjured them from acting in a way that would cause harm to God, to others, and to themselves.
Rarely are people capable of separating the sin from the sinner. They equate condemning the sin as condeming the sinner. That is why they justify the wolf-pack attack in their own minds, why they see it as alright bringing up past trangressions as proof of the worthiness of the present-day person they're attacking, why compassion becomes in their mouths words of self-righteous superiority. People who truly put themselves in the other person's shoes, who see themselves as full of sin as the one they're attacking, could not use the wolf-pack method, for it would hurt them as much as it hurts their target.
In the end, Jesus sent the others away and forgave the adulteress, this, in spite of the fact that his definition of adultery is more onerous than Moses'. Yet he did not call for reconciliation. (Forgiveness and reconciliation are not one and the same, like many imply when they talk about forgiving and then forget the repenting part.) Instead he called for a new way of thinking and thus living, which may, in time, lead to reconciliation between the adulteress and the people. In time, his words of mercy, having convicted them in this passage, will filter down through the minds of the people and change their way of thinking about sin and who has the right to judge the sinner (even Jesus said he came not to judge, only God judges). And in time, the healing balm of his compassion will cause the adulteress to rethink her poor choices, straighten her spine as she begins to see herself as Jesus did, and make better choices that will draw the people back to her. Because of Jesus intervention, reconciliation is possible.