The ruling on taking back a wife without witnesses or a written document

Question:
The questioner asks: If a man divorces his wife because of a dispute that occurred between them, and then, after the dispute is resolved, he takes her back without telling anyone about it, going to a court, or appointing witnesses, is this taking back valid? And is it obligatory for him to write it down, or not?

Answer:
If the divorce was less than three and he did not take compensation from the woman, meaning he did not take a ransom from the woman, then it is permissible for him to take her back. The taking back is done by words or by action. The taking back by words is better; he says, "I have taken back my wife." Or by action, if he has intercourse with her with the intention of taking her back, that is sufficient. Witnessing is a recommended practice (sunnah); if he appoints witnesses to it, it is a recommended practice (mustahabb), but it is not a condition for the validity of the taking back. Allah the Exalted said: This is from the category of advising and recommending. So if he takes her back without anyone witnessing it, and she is in the waiting period ('iddah), she does not exit the waiting period. So his taking her back is valid, on the condition that the divorce was less than three and that he did not take compensation from the woman or from anyone else in exchange for the divorce.