When a person gives three talaqs to his wife, she becomes haram for him. Neither he has the right to take her back in iddah period nor can he solemnize new nikah in iddah or after iddah. A woman divorced thrice, can marry anywhere she wishes beside the person who has given her three talaqs. If the second husband after having intercourse dies or gives talaq and the iddah is over then she deserves the right to do new nikah. If she wishes, she can marry her first husband. There is no other way except it for making the woman halal for the first husband who has given three talaqs to her,. Thus, it is proved from Bukhari Sharif vol. 2, p. 791, fatawa Hindiya vol. 1, p 501, also, other fiqh and fatawa books and from the commentary of hadith. Also it is proved from the holy Quran:
فَإِن طَلَّقَهَا فَلاَ تَحِلُّ لَهُ مِن بَعْدُ حَتَّىَ تَنكِحَ زَوْجاً غَيْرَهُ [البقرة : 230]
For detail see the commentary of the said verse “Ahkamul Quran by Jassas (رحمة الله عليه).
(2) What is the way of arranged halalah before you?
(3) It is haram for her to do new nikah with her first husband during the iddah period of the second husband and the unlawfulness of intercourse is obvious.
Allah (Subhana Wa Ta’ala) knows Best
Darul Uloom Deoband