Before answering this question, I should advise this brother about this conduct and foolishness. The fact that he uttered the words of zihaar and divorced her three times, before the marriage contract was done and just because he was told that a proposal had been made to her on his behalf, is to be regarded as a sign of serious haste and foolishness. The wise and resolute person is the one who controls himself and does not do anything except that which leads to good consequences. How many people have been overcome by foolishness and anger and done things which they regret later on.
With regard to what he did of zihaar and divorcing this woman with whom he had not done the marriage contract, it does not amount to anything, because divorce cannot happen except after the marriage contract, because Allaah says (interpretation of the meaning): “O you who believe! When you marry believing women, and then divorce them before you have sexual intercourse with them” [al-Ahzaab 33:49]. And because divorce is for the one who has the right of intimacy with a woman, and he did not have the right to intimacy until then and did not have a marriage contract; and because divorce is undoing the marriage contract, and so long as he has not got married, there is nothing to be undone.
With regard to zihaar, Allaah says (interpretation of the meaning): “And those who make unlawful to them (their wives) by Zihaar” [al-Mujaadilah 58:3]. So zihaar is connected to their wives, and so long as the marriage contract has not been done with a woman, she is not one of his wives, so zihaar cannot apply to her. But if this man intended by means of zihaar to refrain from having intercourse with her, then he must offer expiation for breaking an oath (kafaarat yameen) if he had married her and had intercourse with her, so as to be on the safe side and so as to discharge any obligation. As for his zihaar, it is not binding, because she is not one of his wives. Expiation for breaking an oath is freeing a slave, or feeding ten poor persons, or clothing them. If he cannot do that, then he must fast for three consecutive days. End quote.
Shaykh Muhammad ibn ‘Uthaymeen (may Allaah have mercy on him).