Does a divorce take place if a man swears to his wife by divorce that if she greets a man from outside the family, then she greets a relative of hers, thinking he is a close relative, then it becomes clear to her that he is not, knowing that the oath was intended as a threat and was made in a state of anger?

If the wife greeted a relative, unaware that it constituted breaking an oath, then there is a difference of opinion among scholars regarding the occurrence of divorce. Some verified scholars have favored its non-occurrence, citing the words of Sheikh Al-Islam Ibn Taymiyyah: "Likewise, whoever forgets an oath; or believes that what he did is not what was sworn upon; due to interpretation; or error: such as hearing and the like: he has not violated the oath, so he is not considered to have sworn." As for greeting a man, if the intention is to shake hands, then it is not permissible for non-mahram individuals. However, if it is merely exchanging greetings without shaking hands, the preponderant view is that it is permissible, provided there is no fear of temptation.