A brain surgeon has to be extremely knowledgeable and study for years to achieve a certain degree of excellence and precision, of course. Why? Because one wrong move could, chas veshalom (God forbid), render his patient brain-damaged forever. So, too, when you're dealing with relevant halachot (Jewish law)—when it comes to sensitive areas like shidduchim (marriage match), giving and asking for information, and looking into a potential shidduch—one wrong word, one extra word, or one wrong tone of voice can affect the lives of two families forever.
So let's talk about revealing information about a potential shidduch. There are three main categories of information that come up in Halacha when it comes to relaying such information. Tonight I want to talk about the first one, which is crucial information. Crucial information is classified as very important information that could have a tremendous, devastating impact on the lives of the couple if they were to marry. For example, what's called crucial information? Medical problems, maybe. Or serious character flaws, such as immodesty, a terrible temper, or a lack of religious observance.
Now, let's take this from the top. We'll start with someone who has a medical problem. The Chafetz Chaim warns us: if the medical problem you're aware of is so confidential that nobody in the community knows anything about it, then you should actually try to stop the shidduch without revealing the confidential information. If you had another way to break the shidduch, do it without letting the cat out of the bag. However, if this isn't the case—if the person they're asking you about had medical problems that people are aware of—you are obligated to say so, even if you aren't asked, as long as the information is 100% accurate. You have to make sure that it's current and not past information, which is extremely important, especially when it comes to medical issues. When in doubt, it's best to ask a rabbi a she'elah (question) about exactly how to go about this and how to say it.
You're not allowed to exaggerate. Even one exaggerated word is already assur (forbidden). Your purpose for giving over the information is solely and strictly for shidduch purposes, but if, God forbid, you had some sort of vendetta against this person, even though you might be right about their medical condition, you are no longer allowed to offer it. Say it. Be sure that the information you're giving over is given in the least harmful way, meaning say just what needs to be said and no more for the sake of the shidduch. Don't add anything, even if it's not an exaggeration. Try to reveal only the least amount of negative information possible.
Again, a serious medical problem is classified in the category we called crucial information. Therefore, if you know a shidduch is going on, even if they didn't ask you, and you know that one party has very serious medical problems, you have to offer the information. The Chafetz Chaim tells us something very powerful. As much as a person has to be so careful not to destroy a shidduch, you have to be equally cautious and careful to make sure that a detrimental shidduch does not go through. Such a shidduch can cause untold heartache and pain for both people for an entire lifetime.