In order for the funeral prayer to be valid, it is essential that one be in a state of purity and free from impurity, which is achieved by doing wudoo’ or by doing tayammum if water is not available or one is unable to use it, according to the majority of fuqaha’. Some scholars narrated that there was consensus on this point, because of the evidence which indicates that tahaarah (purity) is essential for salaah (prayer), and the funeral prayer is also salaah, so it is essential to be in a state of purity.
Some of the scholars are of the view that it is permissible to do tayammum if there is the fear that one may miss the funeral prayer by taking too long to do wudoo’.
As for the view that the funeral prayer may be offered without wduoo’ or tayammum, this is attributed to al-Shi’bi and Ibn Jareer al-Tabari, but it is an invalid view.
Al-Nawawi (may Allaah have mercy on him) said in al-Majmoo’ (5/181): We have stated that our view is that the funeral prayer is not valid unless one is in a state of purity. What this means is that if one is able to do wudoo’, the prayer is not valid without it, and if he is unable to do wudoo’ he should do tayammum. Tayammum is not valid when it is possible to use water, even if he fears that he will run out of time and miss the prayer. This is the view of Maalik, Abu Thawr and Ibn al-Mundhir.
Abu Haneefah said: It is permissible to do tayammum for it even when water is available, if he fears that he will miss it if he takes too long to do wudoo’. Ibn al-Mundhir narrated that from ‘Ata’, Saalim, al-Zuhri, ‘Ikrimah, al-Nakha’i, Sa’d ibn Ibraaheem, Yahya al-Ansaari, Rabee’ah, al-Layth, al-Thawri, al-Awzaa’i, Ishaaq and ashaab al-ra’y, and it is narrated in one report from Ahmad.
Al-Shi’bi, Muhammad ibn Jareer al-Tabari and the Shi’ah said that it is permissible to offer the funeral prayer without being in a state of purity, even if one is able to do wudoo’ or tayammum, because it is a du’aa’. The author of al-Haawi and others said: What al-Shi’bi said is a view that is contrary to consensus, so no attention should be paid to it.
Our evidence that purification is essential is the words of Allaah (interpretation of the meaning): “And never (O Muhammad صلى الله عليه وسلم) pray (funeral prayer) [wa la tusalli] for any of them (hypocrites) who dies” [al-Tawbah 9:84]; so He called it salaah (prayer). In al-Saheehayn it is narrated that the Prophet (peace and blessings of Allaah be upon him) said: “Offer the (funeral) prayer for your companion (sallu ‘ala saahibikum).” And he (peace and blessings of Allaah be upon him) said: “Whoever offer the funeral prayer (man salla ‘ala janaazah) …”, and in other ahaadeeth he called it salaah (prayer). Allaah says (interpretation of the meaning): “When you intend to offer As-Salaah (the prayer) [idha qumtum ila al-salaah], wash your faces and your hands (forearms)” [al-Maa’idah 5:6]. In al-Saheeh, the Prophet (peace and blessings of Allaah be upon him) said: “Allaah does not accept any prayer (salaah) without purification.” The fact that much of its purpose is supplication (for the deceased) does not cancel out the fact that it is a prayer (salaah). End quote.
And Allaah knows best.