In addition to his contributions to Kalam, Shaikh Mufid was a great jurist as well. An interesting incident that demonstrates his unbelievable quick thinking and vast knowledge is when a man asked him how many ghusls (ritual baths) can be hypothetically be mandatory or recommended for a person at one point. The Shaikh told him that the answer was 20. When the man inquired how, Shaikh immediately explained his answer.
The first ghusl, he explained, is mandatory because the person has had a wet dream.
The second is mandatory because he engaged in sexual intercourse with his wife last night.
The third one is mandatory because he had touched a dead body before it had been washed.
The fourth one is recommended because he had touched a dead body after it had been washed.
The fifth one is recommended because the man is in fact a traveler on his way to Medina, and there is a recommended ghusl for entering Medina.
The sixth one is recommended because he is planning on visiting the grave of the Prophet (pbuh).
The seventh one is recommended because he is planning on visiting the grave of the Imams in Baqi.
The eighth one is recommended because today is Eid al-Adha.
The ninth one is recommended because it is also a Friday.
The tenth one is the recommended make-up ghusl which he had missed yesterday, which was Yom al-Arafa (Day of Arafa, and the martyrdom of Muslim bin Aqeel).
The eleventh one is mandatory because there was a complete solar eclipse earlier today.
The twelfth one is recommended because he missed his Salatul Ayaat (prayer becoming obligatory in case of an eclipse, natural disaster, etc.) and is now going to make it up; therefore, there is a recommended ghusl for Salatul Ayaat.
The 13th one is recommended because he is planning on doing “Salatul Hajaat” (prayer for a special wish or desire).
The 14th one is recommended because he is planning on doing “Istakhara” (consulting the Divine on an issue).
The 15th one is recommended because he is planning on doing a “Mubahila” (imprecation) with an opponent. (It is regarding this Mubahila that he needs to do the Salatul Hajaat and Istakhara.)
The 16th one is recommended because he is planning on asking for forgiveness in Medina, and it is recommended to perform ghusl before doing that.
The 17th one is recommended because he saw a man hanging on his way to Medina.
The 18th one is recommended because he had killed a specific desert lizard on his way to Medina for which performing ghusl is recommended.
The 19th one is recommended because it hasn’t rained in Medina for a while, and before he performed “Istisqa” (the special invocation for rain), it is recommended to perform ghusl.
The 20th one is recommended because last night he went to sleep intoxicated.
The people were simply speechless. Another time, several of his peers asked him a rather tricky question regarding inheritance.
“A woman married four men, one after the other,” they asked him. “However, when the fourth one died, she has by now received half of their combined wealth instead of a fourth, as the Sharia would dictate. How is this possible?”
“Very simple,” answered the Shaikh immediately. “The four men were brothers. Their total wealth was, for example, 18 dinars: the first one had eight, the second had six, the third had three, and the last had one. When her first husband died, she received a fourth, i.e. two dinars, whereas the other six were equally distributed among his three younger brothers. The second one now had eight, the third one had five, and the fourth one now had three.
“She decided to marry the second one. Shortly thereafter, he died too. Of his eight dinars, she received two (i.e. one-fourth of his wealth), bringing her total to four, whereas the other six were equally distributed between his younger brothers. The third one now had eight, and the fourth one now had six.
She then decided to marry the third brother, who also died shortly. Of his eight dinars, she received two, bringing her total to six. The other six went to the youngest brother, bringing his total to twelve.
“As expected, she then married the fourth brother, who, as expected, also died soon. Of his twelve dinars, she received a fourth (i.e. three dinars), bringing her total to nine, whereas three-fourths went to his other relatives. Thus, she ended up with one-half (nine dinars) of the combined wealth of her former husbands instead of the one-fourth that would be expected.”
The people listening to this were simply astounded. However, the sounds of “God is Great” and “God Bless Muhammad and the Family of Muhammad” truly filled the mosque as the questioners further revealed that they had actually spent several months devising this question in order to test Shaikh al-Mufid’s wit.