What does "the marriage bed is undefiled" mean?

Well, what it says to me is that a married couple are free to make love physically...among other things. However, I don't think certain things were meant to be part of sex at all. I personally find anal sex and bondage degrading and humiliating. Not to mention, anal sex is dangerous for you physically. I don't think it was part of God's plan for us.
I hope that answers your question..

This particualr verse is found in Hebrews13:4

Marriage is honourable in all, and the bed undefiled: but whoremongers and adulterers God will judge.

It means that you are not to have others in your bed, or not sleeping around, or you will be judged by God. not to say what it does to a marriage. It breaks down trust!!!

Simply put. What you do behind closed doors or on your kitchen floor is your business. As long as there are no animals or others of any sort involved. Bondage, if you like that sort of thing. Just be sure to have safe words in case it gets of of hand, etc. Anal... eeer not too safe for us ladies. Would not recommend. Oral, its up to the consenting married adults. Just be sure that what ever you do, be comfortable and not obligated. Goes right back to communication. No forcing of diff acts on both sides, husband and wife. Holla

Well lets put it this way. I heard a preacher put it like this way. Sex isn't just for SELF pleasure. When people do anal it is merely for SELF PLEASURE. When people have intimate sexual intercourse the way God sedigned it, it is a bind betweent man, wife and God. If it doesn't include God it's wrong. Sex represents more than just sex.

to anon what if you get pleasure out of having anal? it would please both of you.

To me it is saying that both spouses are virgins. You know the whole no sex before marriage thing.

I think it means that the marriage bed is just for the husband and wife- no others should be involved.

My pastor, whom I greatly respect, preaches that whatever a husband and wife want to do TOGETHER and just with each other is fine. This means no extra people brought in- in person or in pictures, movies, etc. (no porn). That's what I agree with.

And it should include the fact that both people are virgins although that doesn't happen as much anymore unfortunately.

I feel the need to clarify here that i'm not talking about my own sex life with my husband lol, I appreciate the pointers on anal sex and bondage and such but the question is simply that, a question. I have heard so many different interpretations of this verse it's one that sparks my curiosity in knowing what other people think.

I have no yet heard that it means both spouses are virgins, but that could also be the meaning, it makes sense to me. If both are pure (sexually) than their bed is undefiled.

I think it's talking about sex itself. If two are married and they are intimate then it is undefiled (it does not violate the sanctity of marriage) before the Lord. If they are not married, then it is defiled meaning it violates the sanctity of the people involved; meaning that they have failed to show the proper respect for their holiness of life and character (Godliness) and the rights of marriage.

What the heck is a whoremonger anyway?