Bismillah Al-Rahman Al-Rahiim.

Prophet Muhammad (saw) said:
"The superstructure of Islam is raised on 5 pillars: Testify that there is no God save Allah Alone and that Muhammad is His Messenger, to perform Shalat, Zakat, Fast in the month of Ramadhan, and do Pilgrimage to the Sacred House (Qa'aba) if you have the means for that".

1. Shahadah... Testify that none has the right to be worshipped but Allah (swt), and that Muhammad (saw) is His Messenger.

- There is none on the earth nor in the heavens deserving to be worshipped save Allah (swt) Alone. Allah (swt) is the One True God. One should ask Allah (swt) Alone to grant such blessings (asking for something, Paradise, Happiness (earth and heavens), etc...).

The Quran says:
And your Lord said: "Invoke Me, [i.e. believe in My Oneness (Islamic Monotheism) and ask Me for anything] I will respond to your (invocation). Verily! Those who scorn My worship [i.e. do not invoke Me, and do not believe in My Oneness, (Islamic Monotheism)] they will surely enter Hell in Humiliation!" [40:60]

And the mosques are for Allah (Alone): so invoke not anyone along with Allah. [72:18]

Say (O Muhammad): "Verily, my Salat (prayer), my sacrifice, my living, and my dying are for Allah, the Lord of the Alamin (mankind, jinn and all that exists). He has no partner . And of this I have been commanded, and I am the first of the Muslims." [6:162-163]

You (Alone) we worship, and You (Alone) we ask for help (for each and everything). [1:5]

Prophet Muhammad (saw) said:
"If you ask for anything, ask for it from Allah Alone; if you seek for help, seek it from Allah Alone."

And indeed it has been revealed to you (O Muhammad), as it was to those (Allah's Messengers) before you: "If you join others in worship with Allah, (then) surely (all) your deeds will be in vain, and you will certainly be among the losers." [39:65]

... Verily, whosoever sets up partners (in worship) with Allah, then Allah has forbidden Paradise to him, and the Fire will be his abode. And for the Zalimun (polytheists and wrong-doers) there are no helpers. [5:72]

Say (O Muhammad): "I am only a man like you. It has been revealed to me that your Ilah (God) is One Ilah (God- i.e. Allah). So whoever hopes for the Meeting with his Lord, let him work righteousness and associate none as a partner in the worship of his Lord." [18:110]

... And whatsoever the Messenger  (Muhammad) gives you, take it; and whatsoever he forbids you, abstain (from it). And fear Allah; verily, Allah is Severe in punishment. [59:7]
 

2. Shalat... Compulsory congregational prayers. Dutifully and perfectly.

- Iqamat-as-Shalat (performing prayer). 5 obligatory prayers every day [Morning Prayers (Subh), Noon Prayers (Zuhr), Afternoon Prayers (Asr), Sun-set Prayers (Maghrib), and Evening Prayers (Isha)] to keep himself in relation with Allah (swt), to invoke and implore Him, and to refrain himself from committing lewdness or indecency. These prayers not only ensure mental peace to the Muslim in this present life, but they also pave the way to him to gain eternal happiness in the Hereafter. To perform prayer, one should be clean, wearing clean clothes and pray in a clean place. (physically and morally). Should start practising from the time of 7 years old. Shalat is a duty on the Muslim in all circumstances.

The Quran says:
And they were commanded not, but that they should worship Allah, and worship none but Him Alone (abstaining from ascribing partners to Him), and perform As-Shalat (Iqamat-as-Shalat) and give Zakat, and that is the right religion. [98:5]

Prophet Muhammad (saw) said:
"The obligation which distinguishes between us and the disbelievers is prayer, therefore, whoever desists from prayer, becomes a disbelievers."

- Clean his/her body by taking a bath: Hads Akbar.
- Wudu': Ablution.
- Wearing clean clothes and pray in a clean place. (physically and morally).
- Facing the Qiblah (Qa'aba).
 

3. Zakat... Obligatory Charity.

- Paying the poor-due: Muslim who possesses a certain amount of property, to pay annually the Zakat, of his possessions to the poor or to the other categories of people mentioned in the Holy Quran.

The Quran says:
And they were commanded not, but that they should worship Allah, and worship none but Him Alone (abstaining from ascribing partners to Him), and perform As-Shalat (Iqamat-as-Shalat) and give Zakat, and that is the right religion. [98:5]

It soothes the poor's feelings, satisfies their needs, and strengthens the bonds of mutual love among the poor and the rich. Allah (swt) promised to give the best rewards for those who expend their money for His sake.
 

4. Saum (fasts)... During the month of Ramadhan.

- Fast during the month of Ramadhan, the ninth month of the Hijri calendar. Before the dawn of the first day of Ramadhan, a Muslim intends to fast this month, and abstains every day from drinking, eating, etc... He performs fast till the end of the month of Ramadhan, fuldilling by that the commandment of Allah (swt), and seeking His pleasure.

The Quran says:
O you who believe! Observing As-Saum (the fasting) is prescribed for you as it was prescribed for those before you, that you may become Al-Muttaqun (the pious). [Observing Saum (fasts)] for a fixed number of days, but if any of you is ill or on a journey, the same number (should be made up) from other days. And as for those who can fast difficulty, (e.g. an old man), they have (a choice either to fast or) to feed a Miskin (poor person) (for every day). But whoever does good of his own accord, it is better for him. And that you fast is better fo you if only you know. The month of Ramadhan in which was revealed the Holy Quran, a guidance for mankind and clear proofs for the guidance and the criterion (between right and wrong). So whoever of you sights (the crescent on the first night of ) the month (of Ramadhan i.e. is present at his home), he must observe Saum (fasts) that month, and whoever is ill or on a journey , the same number [of days which one did not observe Saum (fasts) must be made up] from other days. Allah intends for you ease, and He does not want to make things difficult for you. (He wants that you) must complete the same number (of days), and that you must magnify Allah [i.e. to say Takbir (Allahu Akbar; Allah is the Most Great] for having guided you so that you may be grateful to Him. [2:183-185]

"Allah (swt) forgives sins committed by mistake, forgetfulness, or by compulsion."
 

5. Hajj... Whenever one is capable of.

- Hajj (Pilgrimage) is a duty of a Muslim to perform pilgrimage to the Qa'aba once in a lifetime, but it is permissible for him to go on pilgrimage voluntarily more than once.

Pilgrimage has innumerable benefits:
1. In fulfilling this service, man expresses his devotion to Allah (swt), not only by performing rites which need physical effort, but expresses also his deep spiritual devotion to Allah (swt) and spends of his money for His sake.
2. Annual Muslim congress, attended by Muslims from all over the world.
etc...

Meet in one place Makkah; all being dressed in one uniform (Ihram), worshipping Allah (swt), performing the same rites during the fixed period of Hajj. The Qa'aba is the Qiblah of all Muslims.
- Circumambulating round the Qa'aba (7 times), Sa'i (7 times from Safa to Marwah), attending Arafah, Muzdalifah, and staying for several days in Mina... Worship Allah (swt) according to the method He commanded and during the time He fixed.

The Quran says:
... And Hajj (pilgrimage to Makkah) to the House (Qa'aba) is a duty that mankind owes to Allah, those who can afford the expenses (for one's conveyance, provision and residence); and whoever disbelieves [i.e. denies Hajj (pilgrimage to Makkah), then he is a disbeliever of Allah], then Allah stands not in need of any of the Alamin (mankind, jinn and all that exists). [3:97]

Performing Umrah or lesser pilgrimage once in a lifetime is also a duty that a Muslim should fulfil, visit the mosque of the Prophet in Al-Madina, the historical places... advisable deed and whoever performs it will be rewarded by Allah.