There are 6 obligatory acts of ablution, related to the organs of ablution:

  1. Washing the whole face:
    Washing the whole face involves rinsing the mouth and the nose with water. Accordingly, one’s ablution is void if one washes one’s face without rinsing both the mouth and the nose with water. This is because the mouth and the nose belong to the face, and Allah, Exalted be He, says (regarding ablution), “… Wash your faces…” (Qur’an 5:6). Thus, Allah commands washing the whole face during ablution, so whoever disregards washing any part of the face is considered to be disobedient to the Command of Allah, Exalted be He. Moreover, the Prophet (pbuh) used to rinse his mouth and nose with water while performing ablution.
  2. Washing the forearms including the elbows:
    Allah, Exalted be He, says, “… And your forearms to the elbows…” (Qur’an 5:6), i.e. washing them including the elbows, as the Prophet (pbuh) used to do according to a hadith narrated in this regard. It is also stated in another hadith that the Prophet (pbuh) “… washed his hands (during ablution) until he reached the upper arms.” This indicates that the elbows are included when washing the arms during ablution.
  3. Wiping over the whole head:
    Wiping over the head includes the ears, for Allah, Exalted be He, says, “… And wipe over your heads…” (Qur’an 5:6). Moreover, the Prophet (pbuh) said, “The ears are treated as part of the head.” (Related by Ibn Majah, Ad-Daraqutni, and other compilers of Hadith). Therefore, it is incorrect to abandon wiping over the ears, for it is insufficient to wipe over one part of the head and neglect another during ablution.
  4. Washing the feet including the ankles:
    During ablution, the feet must be washed including the ankles, for Allah, Exalted be He, says, “… And wash your feet to the ankles…” (Qur’an 5:6). Here, the preposition ‘to’ means ‘with’ according to the hadiths pointing out how ablution is performed, and through which it is stated that the whole feet must be washed ‘including’ ankles.
  5. Sequence:
    The decreed sequence has to be observed while performing ablution. To clarify, one begins with washing the face, followed by the hands, then wipes over the head, and finally washes the feet, as clearly shown in the verse; Allah, Exalted be He, says: “O you who have believed, when you rise to [perform] prayer, wash your faces and your forearms to the elbows and wipe over your heads and wash your feet to the ankles.” – Qur’an 5:6. The Prophet (pbuh) used to follow that order while performing ablution, saying: “This is an ablution without which Allah does not accept any prayer.” – Related by Abu Dawud and other compilers of Hadith.
  6. Succession:
    This means to wash the organs successively without any interval between washing two organs, i.e. the organs must be washed successively without pause, as much as possible.

These are the obligatory acts of ablution that must be fulfilled as commanded by Allah in His Ever-Glorious Book, the Qur’an.

Scholars disagree concerning the ruling on tasmiyah upon starting ablution; they differ whether it is an act of the Sunnah or an obligatory practice of ablution. At any rate, according to all Muslim scholars, it is permissible to start ablution with tasmiyah and it should not be abandoned.

The reason behind specifying those four organs for ablution (i.e. the face, hands, head, and the feet) may be because they are the commonest bodily parts related to sins, so their physical purification may be an indication of spiritual purification (from the sins committed by them). The Prophet (pbuh) has stated that whenever a Muslim washes one of these organs (during ablution), the misdeeds committed through it are remitted and that such misdeeds fall and vanish with the flow of the water used for washing that organ, until the last drop fit. In addition, the Prophet (pbuh) enjoined saying the Two Testifications of Faith following washing these organs (i.e. following ablution) as a sign of combining both physical and spiritual purity. The physical purity is achieved through washing those organs in the way prescribed by Allah in His Ever-Glorious Book, the Qur’an. As for the spiritual purity, it is achieved by uttering the Two Testifications of Faith that purify on from polytheism and disbelief.

In the last part of the aforesaid verse related to ablution, Allah, Exalted be He, says:

“…Allah does not intend to make difficulty for you, but He intends to purify you and complete His favor upon you that you may be grateful.” – Qur’an 5:6.

Thus, gentle reader, every Muslim has to know that Allah has decreed ablution in order to purify them from sins, and to complete His favor upon them. Likewise, if you contemplate the opening of the same verse, “O you who have believed…” you will find that it is a generous, gentle call through which Allah, Glorified be He, addresses those who have faith, as they are the ones who will listen to, obey, abide by and benefit from what Allah says and enjoins.

That was why the Prophet (pbuh) said:

“No one keeps being in a state of ablution except the believer.” Ibn Majah 1/178.

Along with the obligatory acts of ablution you should also know the sunnah acts in order to fully understand how Prophet Muhammad (phuh) used to perform Ablution.

Also read – The Sunnah Acts of Ablution
And read – How to Perform Ablution?