Verse 24:3 from the light

Stoning to death is only for married adulterers. That is if they fail to produce four witnesses and are found guilty. This is a deterrent as it would be very difficult to produce four independent witnesses of your adultery.

The verse you've quoted is for unmarried men. See the tasfir below.

* تفسير Tanw�r al-Miqb�s min Tafs�r Ibn �Abb�s
{ ٱلزَّانِي لاَ يَنكِحُ إِلاَّ زَانِيَةً أَوْ مُشْرِكَةً وَٱلزَّانِيَةُ لاَ يَنكِحُهَآ إِلاَّ زَانٍ أَوْ مُشْرِكٌ وَحُرِّمَ ذٰلِكَ عَلَى ٱلْمُؤْمِنِينَ }

(The adulterer) from the people of the Book who admits his crime (shall not marry save an adulteress) from the slaves of the people of the Book (or an idolatress) from the slaves of the Arab idolaters, (and the adulteress none shall marry save an adulterer) from the people of the Book (or an idolater) from the Arab idolaters. (All that) marrying the slaves of the people of the Book and the slaves of Arab idolaters (is forbidden unto believers) this verse was revealed about a group among the Companions of the Prophet (pbuh) who wanted to marry some slaves from the people of the Book and Arab idolaters in Medina. These slaves were known adulteresses but these prophetic Companions wanted to marry them in order to win them over. When this verse was revealed they refrained from marrying them.

http://www.altafsir.com/Tafasir.asp?tMadhNo=2&tTafsirNo=73&tSoraNo=24&tAyahNo=3&tDisplay=yes&UserProfile=0&LanguageId=2

Samuel wrote: thank you for your help (ps i presume you mean if they do produce 4 witnesses and are therefore found guilty ) ok so if a a marriage now takes place between 2 people in this situation is the marriage still valid and complete with the normal rules of marriage and with the full protection of muslim community and who would officiate and register such a marriage?

How would people know that these two who want to get married are fornicators? If they are not found out and if they do not admit their sins to anybody then they are free to marry. Also in Islam, a sin is a private matter between the person who commits the sin and His Maker Allah Subhana Wa Ta'ala.

I suspect that marriages are happening everyday between fornicators. How could anyone stop such a thing?

You don't seem to understand the context in which this verse was revealed.

Read the tasfir very carefully.

Samuel wrote: i understand the context but the wording of the verse clearly seems to be not only written for the context but also to set a precedent about what are to be accepted as suitable marriages. where does it imply this is written for one event in history and if such surely a shorter no as an answer would have sufficed for the companions and their plan to marry the slaves. Or are you saying that the Quran is only applicable to the context and times revealed. I don't think this is how muslims see the Quaranic verses so the question of marriages of this sort still stands unless you can say for certain this verse is context limited and the proof of this. As a side note how much of the Quran is to be context only applied ?

Look a true believer will not marry a known fornicator. Unless that believer is a truly pious person and the fornicator has sought forgiveness from Allah Subhana Wa Ta'ala. Otherwise it's clearly forbidden.

I don't know what you are trying to drive here.