Dear brothers!  Know that purification is the key of Salaah (prayer) and the most important condition of its validity. Allah the Almighty says in the Qur’an which translates as: “O you who believe! When you prepare for prayer, wash your faces, and your hands (and arms) to the elbows; rub your heads (with water); and (wash) your feet to the ankles. If you are in a state of ceremonial impurity, bathe your whole body. 
In this verse, Allah orders purification from minor impurities by Wudhu and from major impurities by Ghusl  ahead of Salaah. The above verse indicates that purification from both types of impurities can be made by pure water if it is available and there is the ability to use it, 
The wisdom of washing these particular parts of the body during Wudhu  is because they are the most likely used in doing all actions. With these parts, a man may obey or disobey Allah. They are the quickest parts of the body stirred to either obedience or disobedience. The Prophet (Salla Allahu Alaihi Wa Sallam) reported that whenever one of those parts is washed in ablution, a sin committed by such part is removed.
Thus, Allah showed the wisdom of this commandment  to purify Muslims from impurities and from sins. In a Hadith, it was narrated that the people of this Ummah will be resurrected with bright faces, hands, and feet due to the traces of ablution. They will be distinctive among other peoples (nations) by this sign. This is an indication of ablution and its benefit for Muslims in this life and in the Hereafter.
It was narrated from ‘Umar bin Al-Khattab (may Allah be pleased with him) that the Prophet (Salla Allahu Alaihi Wa Sallam) said: “Whoever of you performs ablution thoroughly then says: I testify that there is no god but Allah, with Whom there is no associate, and that Muhammad is His servant and Messenger, the eight gates of Paradise will be opened to him to enter from whichever he wants” (Ahmad and Muslim). 
In another narration, the following addition is made: “O Allah! Make me among the oft repentant and the oft purified (Allahumma aj’alni minat-tawwabin waj’alni minal-mutatahhirin). The wisdom of this invocation following ablution is to join the internal purification of testifying to Allah’s Oneness and the external purification of performing ablution.
Servants of Allah! Keep on performing purification before prayer, and purify yourselves as Allah commanded you, and follow the example of the Messenger of Allah (Salla Allahu Alaihi Wa Sallam). As Allah says which translates as: “And obey Allah and the Messenger; that you may obtain mercy” (Aal-Imran: 132).
May Allah bless us through the guidance of the Holy Qur’an.