There are many times and situations in which it is recommended to perform wudu. Here are some of them:
1. When you wish to read or carry the books of tafsir and hadith, out of veneration for the speech of Allah and His Messenger ﷺ . Allah says: If someone venerates the things Allah has made sacred, this is truly a sign of piety in the heart (22:32). When Imam Malik was asked to narrate hadith, he would perform ghusl, put on perfume and put on his best clothes before doing so. This shows you the secret of adab (correct etiquette) which is a means of elevation. When Muslims neglected these etiquettes they lost out on great good. They lost the spirit of their acts of worship while the outward form remained. One of the knowers of Allah said: “The religion is veneration for the religion.” The degree to which you benefit from any act of worship is according to the degree of your veneration for that act of worship.
2. When you wish to remember Allah. The scholars are in agreement that it is permissible to remember Allah in a state of minor and major ritual impurity (janabah). However, it is recommended to be in a state of wudu when you remember your Lord.
One of the Companions once gave the Prophet ﷺ greetings of salam while he was making wudu. The Prophet did not respond until he had finished his wudu. He said that what had prevented him from responding was that he did not wish to remember Allah while not in a state of wudu. Saying: “Peace be upon you and the mercy and blessings of Allah,” constitutes remembrance of Allah and ‘al-Salam’ is one of the names of Allah.
You should have a time during the day or night in which you remember Allah in the best possible state: in wudu, with tranquillity and facing the qiblah. You should also remember Allah in other states –when you are in a state of minor or major ritual impurity, when you are lying down, when you are walking and so on. The Prophet ﷺ would remember Allah in every state.
3. When you wish to study the sacred sciences, because the light of the Qur’an and the Sunnah extends to them. Someone who is studying Arabic grammar in order to be able to understand the Qur’an and the Sunnah, for example, should do so in a state of wudu. He should be in a state of wudu not just when he attends the lesson but also when he reviews it.
4. When you wish to recite the Qur’an without touching the mushaf or when you wish to listen to the Qur’an, although it is permissible to do both while not in a state of wudu.
5. Before sleeping. The Prophet ﷺ said: “When you go to your bed, perform wudu as you would for prayer.” If someone is in a state of major ritual impurity it is strongly recommended for him to make wudu before sleeping, just as it is recommended for him to make wudu before eating and drinking.
6. When you become angry. The Messenger of Allah ﷺ said: “Anger is from the Devil and the Devil was created from fire. Water puts out fire, so if one of you becomes angry, then he should perform wudu.” In general when someone’s normal state changes they should perform wudu to help them to return to a state of calmness and balance.
7. After forbidden speech, such as backbiting, tale-bearing or lying. Some Zaydi scholars are of the opinion that lying and backbiting invalidate a person’s wudu. So if you want to know if someone is telling the truth about something you wait for him to make wudu and then ask him about that thing. If he goes to make wudu again before praying it means he was lying.
8. After committing a sin
9. When you wish to perform ghusl it is recommended to perform wudu first
10. Before giving the adhan. It is disliked (makruh) to give the adhan while not in a state of wudu, and even more disliked to give the iqamah while not in a state of wudu.
11. Before spending time in the mosque. It is impermissible to spend time in the mosque in a state of major ritual impurity
12. Before performing Sa`i between Safa and Marwah
13. Before visiting graves in general and the grave of the Prophet Muhammad ﷺ and any other prophet specifically. Imam Malik said that people should say they are visiting the Prophet and not merely his grave. One of the Companions came and kissed the grave of the Prophet and rubbed his face against it. When asked what he was doing he said: “I did not come for the sake of the earth or the stone. I came to the Messenger of Allah.”
14. After touching or carrying a dead person
15. After cupping, vomiting and eating camel’s meat due to the fact that some scholars are of the opinion that these things invalidate your wudu.
Extracts from Sayyidi Habib Umar bin Hafiz’s classes on the rulings and etiquettes of purification from Habib Abdullah bin Husayn Balfaqih’s “Kifayat al-Raghib” in Shafi fiqh.