Fiqh-us-Sunnah Volume 3, Zakaat and Fasting, Fiqh 3.152A.
The following acts are permissible for one who is making i’tikaf:
1. The person may leave his place of i’tikaf to bid farewell to his wife. Safiyyah reported: “The Prophet was performing i’tikaf and I went to visit him during the night. I talked to him and then I got up to go. He got up with me and accompanied me to my house. (Her residence was in the house of Usamah ibn Zaid. Two men of the Ansar passed by them and when they saw the Prophet they quickened their pace.) The Prophet said: ‘Hold on, she is Safiyyah bint Haya.’ They said: ‘Glory be to Allah, O Messenger of Allah we did not have any doubt about you].’ The Prophet, upon whom be peace, said: ‘Satan flows in the person like blood. I feared that he might have whispered some [slander] into your heart.'” This is related by al-Bukhari, Muslim, and Abu Dawud.
2. Combing and cutting one’s hair, clipping one’s nails, cleaning one’s body, wearing nice clothes or wearing perfume are all permissible. ‘Aishah reported: “The Prophet was performing i’tikaf and he would put his head out through the opening to my room and I would clean [or comb in one narration] his hair. I was menstruating at the time.” This is related by al-Bukhari, Muslim, and Abu Dawud.
3. The person may go out for some need that he must perform. ‘Aishah reported: “When the Prophet performed i’tikaf, he brought his head close to me so I could comb his hair, and he would not enter the house except to fulfil the needs a person has.” This is related by al-Bukhari, Muslim, and others.
Ibn al-Munzhir says: “The scholars agree that the one who performs i’tikaf may leave the mosque in order to answer the call of nature, for this is something that he personally must perform, and he cannot do it in the mosque. Also, if he needs to eat or drink and there is no one to bring him his food, he may leave to get it. If one needs to vomit, he may leave the mosque to do so. For anything that he must do but cannot do in the mosque, he can leave it, and such acts will not void his i’tikaf, even if they take a long time. Examples of these types of acts would include washing one’s self from sexual defilement and cleaning his body or clothes from impurities.”
Sa’id ibn Mansur records that ‘Ali said: “If a person is performing i’tikaf, he is to attend the Friday congregational prayer, be present at funerals, visit the ill and go to see his family about matters that are necessary, but he is to remain standing [while visiting them].” ‘Ali helped his nephew by giving him 700 dirhams to buy a servant and the nephew said: “I am performing i’tikaf “. ‘Ali said: “What blame would there be upon you if you go to the market to buy one?” Qatadah used to permit the person who was performing i’tikaf to follow the funeral procession and to visit the sick, but not to sit while doing so. Ibrahim an-Nakha’i says that they preferred that the person who was performing i’tikaf do the following deeds and he was allowed to do them even if he did not do them to visit the sick, to attend the Friday prayers, to witness the funerals, to go out to meet his needs, and not to enter a place that has a ceiling. He said: “The one who is performing i’tikaf should not enter a roofed place unless there is a need to do so.” Al-Khattabi says: “A group of people say that the person performing i’tikaf may attend the Friday prayer, visit the ill, and witness funerals. This has been related from ‘Ali, and it is the opinion of Sa’id ibn Jubair, al-Hassan al-Basri, and an-Nakha’i.” Abu Dawud records from ‘Aishah that the Prophet would visit the sick while performing i’tikaf. He would visit them without steering away from his path. It has also been related from her that it is sunnah for the person not to leave his place of i’tikaf and visit the sick. This means that the person is not to leave his place of i’tikaf with the sole intention of visiting the sick, but if he passes by him, he may ask about him provided it is not out of his way.
4. The person may eat, drink, and sleep in the mosque, and he should also keep it clean. He may make contracts for marriage, buying, selling, and so on.