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, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.
If the questioner here means that this man divorced his wife, with whom he did not consummate the marriage, thrice, with one pronouncement of divorce, then the three divorces are effected, and she, consequently, becomes irrevocably divorced from him, according to the opinion of the majority of scholars, including the four leading Imaams (of Fiqh). According to their opinion, this woman is not lawful for him unless she marries another husband first.
However, Shaykhul-Islam Ibn Taymiyyah disagreed with that opinion when he stated that only one divorce is effected by divorcing thrice with one pronouncement. According to his opinion, it is permissible for that man to remarry that woman, with a new marriage contract and a new dowry.
On the other hand, if the questioner means that the man divorced his wife once for the first time, and then divorced her again and again but not one after the other directly with three separate pronouncements in the same session, in this case, it is only the first divorce which would be effected, for it is only by the first divorce that the wife with whom he did not consummate the marriage would become irrevocably divorced from him, and the following divorces would be meaningless, since they were done for nothing.
This is agreed upon between the four leading Imaams. If it reoccurs but not one after the other directly (in one session), the divorce is revocable according to Abu Haneefah and Ash-Shaafi‘i . And we believe that this is the predominant opinion. Henceforth, the divorce is revocable, and it is permissible for her husband to remarry her with a new marriage contract and dowry and no ‘Iddah is due on her, for she was divorced before the consummation of marriage.