Is it permissible to enjoy a wife during menses, without having intercourse and she reaches orgasm? Is it permissible if I go to my wife after she stopped menstruating but has not taken bath/purified her? Can I lie over my wife and enjoy without any intercourse?

During the time of menstruation a husband can seek enjoyment with his wife except that his wife should wear a cloth covering from her navel to her knees. The rest of the body can be used for enjoyment. After finishing the days of menstruation if enough time passes over the woman wherein she is able to take a shower and perform a prayer and then before taking a shower her husband can cohabit with her.
The answer to your third question is that it is permissible in the Islamic law.
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