This is a beautiful verse about the way a marriage should be handled. I'm still trying to figure out how to get Greek letters in here...
But Young's Literal Translation (awkward but accurate) says:
Defraud not one another, except by consent for a time, that ye may be free for fasting and prayer, and again may come together, that the Adversary may not tempt you because of your incontinence;
A couple of things really popped out at me...
Defraud is just like it sounds. I've done some studies on Old Testament marriage contracts and there were three things that were always guaranteed. A home (the husband provides and the wife maintains), food/oil (the husband provides and the woman prepares) and bed (sexual relations). These three things were so important, if any of these three were denied on a regular basis, it was grounds for divorce. To enter into a marriage and refuse the marraige bed was to defraud the mate of marital rights.
except by consent: this really caught my eye, concerning marriage in general.
sumphonou - sounds like "symphony" and means, in harmonious accord. Isn't that the way a marriage should work? Each half of the whole striving to be in harmonious accord. Just like the word that we get from this, symphony - it doesn't imply that you are in lockstep. Just like a symphony, each partner plays his or her own instrument. One time, one will have the melody, another time, the other will. And each time, their mate will be behind them, harmonizing, supporting. A symphony wouldn't be a symphony if everyone played the same note! So it is with marriage.
pros kairos hina scholazo - for a limited time, in order to give oneself to
fasting and prayer
and again may come together, (be one flesh, husband and wife, give one another comfort and pleasure)
that the Adversary may not tempt you because of your incontinence; How many people have fallen, because their spouse didn't pay attention to the consequences of denying their other half? I submit that a husband or wife that denied his or her spouse is a stumbling block the likes of which few people ever see.
This verse communicates the importance of "one-flesh-ness" and the importance of setting it aside only for the things of God, and then only for limited times.
I would submit that a husband or wife should not have to go without marital relations (unless there are special circumstances that prohibit them) for any longer than they also expect their husband and wife to go without food. There is no reason for denying one's spouse the comfort and pleasure that a marriage bed should bring. (The last paragraph has been edited just because it was an awkward sentence and didn't quite say what I wanted it to say.