Had sex with his divorcée thinking that divorce in menses does not count
10-2-2011 | IslamWeb
Question:
asalaamu alaikum My husband is married to me and another sister.In May 2009 he pronounced the third talaq the following day she informed him her mense was on when he pronounced the divorce. My husband then said the divorce does nt count.Howeva upon reseach he found out and spoke with an imam that the divorce count thru innovation. Its sinful but still counts.He found out the information in Oct. Prior to that information he slept wit her was around her uncovered.My question is did he commit ZINA or since he did know the proper information theirs no sin on him??? inshaALLAH I hope to hear from you.
Answer:
All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad 
is His slave and Messenger.
Your husband should have asked the scholars before having sexual intercourse with his wife after he had divorced her thrice based on his belief that divorce in menses is not effective. Allaah Says (what means): {…so ask the people of the message if you do not know.}[Quran 16:43] Besides, the Prophet said: “Why did they not ask if they did not know; the cure for ignorance is to ask (someone who knows).” [Abu Daawood]
Therefore, it was not permissible for him to have sexual intercourse with his wife after the third divorce unless he acted according to the view of the scholars who are trustworthy in terms of knowledge and piety and who are of the opinion that this is not forbidden. That is because it is permissible for the common person to act according to the view of the scholars whom he asked and act according to the Fatwa that they issued to him.
Based on this, if he did not know the ruling and did what he did while being negligent in regard to asking the scholars, then he is sinful. However, if he was acting according to the view which he thought to be correct, then he is not sinful.
Allaah Knows best.