Setting
1- A man divorced his wife three times, then another man married her and divorced her before consummating the marriage with her. Her first husband wanted to remarry her, and the Prophet (may Allah's peace and blessings be upon him) was asked about that. He said: No, not until the second husband tastes of her sweetness what the first one tasted
2- Three things are binding regardless of whether they were expressed seriously or jokingly: marriage, divorce, and restoration (of a divorcee)
3- The son of Adam cannot make a vow concerning what is not his; he cannot free a slave who is not his; and he cannot divorce a woman who is not his (wife)
4- No financial maintenance is due to you upon him
5- Divorce whomever of them you wish