"So is the one who goes into his neighbor's wife; whoever touches her will not go unpunished"
Solomon has just listed two impossible scenarios to demonstrate the danger and sure punishment that comes with adultery. He asks if a person can have a piece of wood that is on fire inside next to his skin and not have his clothing catch on fire. The obvious answer is: “No, it is not possible.” The second scenario that he sets up is: Is it possible to walk across hot coals and not scorch your feet? The answer is: “No.”
This proverb in verse 29 is the conclusion to this line of instruction about adultery. DO NOT THINK YOU WILL GET AWAY WITH IT. I have had the unfortunate assignment of dealing with a number of people who were caught in adultery. It is always exposed. It always causes significant damage to everybody connected to the affair. It was exciting for a short period of time, but let me tell you the consequences and punishments last a whole lot longer than the pleasure.
This is the Hebrew word naga which means touch or reach. The word touch clearly means reach out for in a sexual or intimate way. This is very similar to the Apostle Paul's admonition in 1 Corinthians 7:1 It is good for a man not to touch a woman. It is not that he is saying that physical touch of someone else’s wife is outlawed, but touch that has any sensual or erotic connection is outside of the boundaries of moral behavior.
This is the Hebrew word naqah which means to be clear, empty, clean, innocent. The word is preceded by the word not or no and reads they will not be innocent or free. Solomon is forcing the would-be adulterer to see what they never think about. You will be caught and there will be significant consequences. I can't tell you how many people I have talked to who have committed this sin and when the consequences start piling up, they all want to go back to before they did this thing.
There are financial punishments, relational punishments, marital punishments, vocational punishments, spiritual punishments, mental punishments, and many others.
If you are in a place right now where you are tempted to commit adultery, get out of that relationship in any way you can. Do not go through with it. If you are in an adulterous relationship, then stop it. Every day you don't allow it to continue reduces the amount of the pain and consequences that are coming. I know that this person has become dear to you and you do not know what you will do without this person, but it is a mistake. There is not an easy way to stop these relationships. Jesus said you just need to cut them off cold turkey. Call the person and say that it is over and you no longer want to see them, talk with them, or have any contact with them anymore. I have found that this is the only way. There is no way to make the other party in adultery understand. It just has to end and now is better than later. The less time the adultery continues, the less the consequences and punishments will be. If you are in one, get out. If you are moving in that direction, stop it. Get away emotionally and physically from that person. If you are attracted to someone who is not your spouse, don't say anything to anyone; just move away from contact of any sort with that person and let those feelings die. There are feelings that should not see the light of day. If you do not act upon them, they will eventually go away. Do not betray yourself and God for some feelings. It is not worth it.