Islam: Creed and Worship
He (Exalted be He) said, And I (Allâh) created not the jinn and mankind except that they should worship Me (Alone).
The Ayah (Qur'anic Verse) at hand implies that the purpose of the creation of the Jinn and mankind is to establish the Oneness of Allah and offer obedience to Allah and avoid sins. This is the worship for which they were created. The most important of the acts of worship is to seek Allah Alone with worship and believe that He is the One and Only Who deserves to be worshipped without anyone other than Him. He (Glorified be He) said,
And your Ilâh (God) is One Ilâh (God - Allâh), Lâ ilâha illa Huwa (there is none who has the right to be worshipped but He), the Most Gracious, the Most Merciful. Allah (Glorified be He) also says: So know (O Muhammad صلى الله عليه وسلم) that, Lâ ilâha illallâh (none has the right to be worshipped but Allâh)
Thereupon, Tawhid is the first and most important obligation. A person should believe that he/she is Allah's slave, seek Him Alone with worship and have firm faith that He is the Truthful God in addition to believing in His Messenger Muhammad (peace be upon him) and testifying that he (peace be upon him) is Allah's Last Messenger to the Jinn and humankind. One should also believe in all that was revealed to the Prophet (peace be upon him).
This is the most important of all Islamic fundamentals and the duty that is required on every accountable person from the Jinn and humankind. All the accountable people from the jinn and humankind should worship Allah Alone and believe that no one is worthy of worship but him, that Muhammad is Allah's Last Messenger. They should also believe that everything revealed to him is the truth. It is necessary to follow in his footsteps until one meets his Lord (glory be to Him). This is the worship for which people are created and it is Taqwa, Iman, Islam,and Birr.
All these are just names that stand for one meaning, namely, the religion of Allah, the religion of guidance, piousness, righteousness, faith, and worship of Allah Alone. All these meanings are involved in this religion.
The religion of Allah is called `Ibadah as it includes submission, humbleness to, and Taqwa of Allah, for the slave of Allah fears Allah's Wrath. It also includes Iman, as it is nothing but having faith in all that Allah and His Messenger informed of, Huda (guidance) for Allah guides people with it to goodness and uprightness, and Birr (righteousness) for it includes every goodness and is the cause of happiness. Allah said assuring these meanings, Verily, the Muttaqûn (the pious. See V.2:2) will be in Gardens (Paradise), and Delight. Allah (Exalted be He) also says: Verily, for the Muttaqûn (the pious - See V.2:2) are Gardens of delight (Paradise) with their Lord.
Indeed, those who realized Taqwa among Muslims are the believers who worshipped Allah (Glorified be He) and fulfilled the meaning of His Saying, And I (Allâh) created not the jinn and mankind except that they should worship Me (Alone).
They deserve this title out of their piety, fulfilling Allah's Right, sincerity to Him, believing in Him and His Messenger Muhammad (peace be upon him) and in what Allah and His Messenger said in the Glorious Book and the Sunnah of His Honest Prophet (peace be upon him). Islam is not complete unless these things are fulfilled in addition to the declaration of faith and the belief that there is no one worthy of worship but Allah whereas other things that are worshipped with Allah are nothing but falsehood. Allah (Exalted be He) said,
That is because Allâh — He is the Truth (the only True God of all that exists, Who has no partners or rivals with Him), and what they (the polytheists) invoke besides Him, it is Bâtil (falsehood).
Moreover, it is necessary to believe in all that Allah and His Messenger said about the events of the past and the future including the accounts of the preceding Prophets, Paradise, Hell, Doomsday, the Reckoning, the reward of the believers, the punishment of the disbelievers, etc.
In other words, everything that is mentioned in the Qur'an or proved to be said by the Prophet (peace be upon him) according to one's knowledge - one should have faith in. After that, one is required to believe in the Truth brought by Prophet Muhammad, have firm belief in the Oneness of Allah, sincerity to Him, and to believe in Allah's Names and Attributes accepting them as reported by Allah and His Messenger without Takyif (descriptive designation of Allah's Attributes), Tahrif (distortion of the meaning), or Tamthil (likening Allah's Attributes to those of His Creation) which is the belief of Ahl-ul-Sunnah wal-Jama`ah (adherents to the Sunnah and the Muslim mainstream).
After that, one should observe what Allah enjoins on His slaves of acts of worship such as Salah (Prayer), Zakah (Obligatory Charity), Sawm (Fasting), Hajj (Pilgrimage), etc. And abide by what Allah and His Messenger ordered and stay away from what they forbid. Allah (Glorified be He) said, O mankind! Be dutiful to your Lord
This is an address to the Jinn and humankind, Arabs and non-Arabs, disbelievers and believers as well. The Ayah means to fear Allah through fulfilling His Commands and avoiding His Prohibitions out of seeking His Pleasure, taking caution from His Punishment, and fearing Allah at all times.
Allah (Exalted and Glorified be He) said, O mankind! Worship your Lord (Allâh), Who created you and those who were before you so that you may become Al-Muttaqûn (the pious - See V.2:2).
It is necessary to worship Allah alone sincerely and truthfully observing His Orders and avoiding His Prohibitions. In some Ayahs, Allah commands the believers in particular saying, O you who believe! Be afraid of Allâh
This call takes place in many Ayahs, as the believers included in the commandment to have piousness. They are more entitled with this commandment than others owing to the fact that they believe in Allah and His Messenger. Therefore, they should perfect this faith and abide by it, until death just as Allah (Glorified be He) said to His Prophet (peace be upon him),
And worship your Lord until there comes unto you the certainty (i.e. death). He (Exalted be He) said,
O you who believe! Fear Allâh (by doing all that He has ordered and by abstaining from all that He has forbidden) as He should be feared. [Obey Him, be thankful to Him, and remember Him always], and die not except in a state of Islâm [as Muslims (with complete submission to Allâh)].
(Part No. 7; Page No. 91 - 92 - 93 - 94)
Fatawa Sheikh Abdul Aziz Ibn Baz