Ablution is done to purify the body against impurities. We perform ablution particularly before offering namaz or before touching mushaf i.e. Quran. The purpose of ablution is to free oneself from the impurities and to become clean before performing a religious activity. But ablution is not only limited to be performed before namaz etc. in fact, for a Muslim to remain pure all the time is more liked because ablution also makes one far from evils and vulgar acts. It is even a sunnah to perform ablution before going to bed.
The normal way of performing ablution is to wipe the parts of body thrice each i.e. to wash hands thrice, and then to wash mouth, nose, face, arms up till elbows, masah and then feet. All these parts of body are washed thrice as per the method of ablution. But it should be kept in mind that if ablution is not performed properly, namaz is not accepted or not valid. This can be proven from a sahi hadith mentioned below:
Bukhari Volume 8, Book 74, Number 268:
Narrated Abu Huraira:
A man entered the mosque while Allah's Apostle was sitting in one side of the mosque. The man prayed, came, and greeted the Prophet. Allah's Apostle said to him, "Wa 'Alaikas Salam (returned his greeting). Go back and pray as you have not prayed (properly)." The man returned, repeated his prayer, came back and greeted the Prophet. The Prophet said, "Wa alaika-s-Salam (returned his greeting). Go back and pray again as you have not prayed (properly)." The man said at the second or third time, "O Allah's Apostle! Kindly teach me how to pray". The Prophet said, "When you stand for prayer, perform ablution properly and then face the Qibla and say Takbir (Allahu-Akbar), and then recite what you know from the Qur'an, and then bow with calmness till you feel at ease then rise from bowing, till you stand straight, and then prostrate calmly (and remain in prostration) till you feel at ease, and then raise (your head) and sit with calmness till you feel at ease and then prostrate with calmness (and remain in prostration) till you feel at ease, and then raise (your head) and sit with calmness till you feel at ease in the sitting position, and do likewise in whole of your prayer." And Abu Usama added, "Till you stand straight." (See Hadith No. 759, Vol.1)
From the hadith mentioned above, it is well proven that if ablution is performed hastily and without proper attention, there are cases that it gets void. So, better to perform ablution properly so that our prayer is accepted.
When one performs ablution, one should not use access water. When we perform ablution, we open the tap and forget to close it till ablution is completed. This is wrong and against sunnah. Whenever our beloved prophet Muhammad s.a.w.w performed ablution it used to be proper and He s.a.w.w never wasted water.
Bukhari Volume 8, Book 75, Number 328:
Narrated Ibn 'Abbas:
One night I slept at the house of Maimuna. The Prophet woke up, answered the call of nature, washed his face and hands, and then slept. He got up (late at night), went to a water skin, opened the mouth thereof and performed ablution not using much water, yet he washed all the parts properly and then offered the prayer. I got up and straightened my back in order that the Prophet might not feel that I was watching him, and then I performed the ablution, and when he got up to offer the prayer, stood on his left. He caught hold of my ear and brought me over to his right side. He offered thirteen Rak'at in all and then lay down and slept till he started blowing out his breath as he used to do when he slept. In the meantime Bilal informed the Prophet of the approaching time for the (Fajr) prayer, and the Prophet offered the Fajr (Morning) prayer without performing new ablution. He used to say in his invocation, Allaihumma ij'al fi qalbi nuran wa fi basari nuran, wa fi sam'i nuran, wa'an yamini nuran, wa'an yasari nuran, wa fawqi nuran, wa tahti nuran, wa amami nuran, wa khalfi nuran, waj'al li nuran." Kuraib (a sub narrator) said, "I have forgotten seven other words, (which the Prophet mentioned in this invocation). I met a man from the offspring of Al-'Abbas and he narrated those seven things to me, mentioning, '(Let there be light in) my nerves, my flesh, my blood, my hair and my body,' and he also mentioned two other things."
So, the sunnan way of performing abltution means to do it properly and to do it without wasting water.
The normal way of performing ablution is to wipe the parts of body thrice each i.e. to wash hands thrice, and then to wash mouth, nose, face, arms up till elbows, masah and then feet. All these parts of body are washed thrice as per the method of ablution. But it should be kept in mind that if ablution is not performed properly, namaz is not accepted or not valid. This can be proven from a sahi hadith mentioned below:
Bukhari Volume 8, Book 74, Number 268:
Narrated Abu Huraira:
A man entered the mosque while Allah's Apostle was sitting in one side of the mosque. The man prayed, came, and greeted the Prophet. Allah's Apostle said to him, "Wa 'Alaikas Salam (returned his greeting). Go back and pray as you have not prayed (properly)." The man returned, repeated his prayer, came back and greeted the Prophet. The Prophet said, "Wa alaika-s-Salam (returned his greeting). Go back and pray again as you have not prayed (properly)." The man said at the second or third time, "O Allah's Apostle! Kindly teach me how to pray". The Prophet said, "When you stand for prayer, perform ablution properly and then face the Qibla and say Takbir (Allahu-Akbar), and then recite what you know from the Qur'an, and then bow with calmness till you feel at ease then rise from bowing, till you stand straight, and then prostrate calmly (and remain in prostration) till you feel at ease, and then raise (your head) and sit with calmness till you feel at ease and then prostrate with calmness (and remain in prostration) till you feel at ease, and then raise (your head) and sit with calmness till you feel at ease in the sitting position, and do likewise in whole of your prayer." And Abu Usama added, "Till you stand straight." (See Hadith No. 759, Vol.1)
From the hadith mentioned above, it is well proven that if ablution is performed hastily and without proper attention, there are cases that it gets void. So, better to perform ablution properly so that our prayer is accepted.
When one performs ablution, one should not use access water. When we perform ablution, we open the tap and forget to close it till ablution is completed. This is wrong and against sunnah. Whenever our beloved prophet Muhammad s.a.w.w performed ablution it used to be proper and He s.a.w.w never wasted water.
Bukhari Volume 8, Book 75, Number 328:
Narrated Ibn 'Abbas:
One night I slept at the house of Maimuna. The Prophet woke up, answered the call of nature, washed his face and hands, and then slept. He got up (late at night), went to a water skin, opened the mouth thereof and performed ablution not using much water, yet he washed all the parts properly and then offered the prayer. I got up and straightened my back in order that the Prophet might not feel that I was watching him, and then I performed the ablution, and when he got up to offer the prayer, stood on his left. He caught hold of my ear and brought me over to his right side. He offered thirteen Rak'at in all and then lay down and slept till he started blowing out his breath as he used to do when he slept. In the meantime Bilal informed the Prophet of the approaching time for the (Fajr) prayer, and the Prophet offered the Fajr (Morning) prayer without performing new ablution. He used to say in his invocation, Allaihumma ij'al fi qalbi nuran wa fi basari nuran, wa fi sam'i nuran, wa'an yamini nuran, wa'an yasari nuran, wa fawqi nuran, wa tahti nuran, wa amami nuran, wa khalfi nuran, waj'al li nuran." Kuraib (a sub narrator) said, "I have forgotten seven other words, (which the Prophet mentioned in this invocation). I met a man from the offspring of Al-'Abbas and he narrated those seven things to me, mentioning, '(Let there be light in) my nerves, my flesh, my blood, my hair and my body,' and he also mentioned two other things."
So, the sunnan way of performing abltution means to do it properly and to do it without wasting water.