Allah, the All Wise, All Knowing, All Merciful and Just, created this Universe in order to test and examine His obedient slaves and reward them, and to punish the disobedient. He Says (what means): "We did not create the heavens and the earth and that between them in play. We did not create them except in truth, but most of them do not know." [Quran 44: 38-39]
Allah also made clear the main goal for the creation of mankind, Saying (what means): "I did not create the Jinn and Mankind except for My worship" [Quran 51: 56]
Allah, the Exalted, did not leave His slaves to rely upon their intellect and inclination to guide them to the correct way; rather He sent them Messengers as bringers of good tidings and warners. He sent the revealed Books with them to be a reference in those matters wherein they disagreed, so that no excuse would remain for the people and the proof would be established against them. Thus, after sending the Messengers, there would be no further excuse for people before Allah.
Indeed, their mission covered every good and banished every evil. They brought to humankind everything needed for their well being and happiness in this world and the Hereafter. There is nothing good, which they did not inform the people about and nothing evil that they did not warn the people against.
‘Abdullaah bin `Amr bin Al-`Aas, may Allah be pleased with him, said that the Prophet said: "There was never a Prophet before me except that it was a duty upon him that he should guide his nation to every good that he knew and warn them against every evil that he knew…" [Muslim]
Indeed, calling to Allah was the mission of the Messengers in order to bring the people out from darkness into light. There are many basic principles upon which their calls were based, which were the starting point for calling to Allah. These fundamental principles are:
1. Tawheed (Monotheism)
3. The Hereafter
Every book revealed by Allah gave great importance to these points. The most important and sublime of these three principles and the most fundamental of them all is Tawheed (Oneness) of Allah.
Allah Says (which means): "And We certainly sent into every nation a Messenger, (saying): 'Worship Allah and avoid Taaghoot (false objects of worship).' " [Quran 16: 36]
Allah has informed us about some of the Prophets, may Allah exalt their mention, and how they faced their people. We see that all of them proceeded upon the universal way laid down by Allah and followed the methodology Allah established for all of them. Not a single one of them is at variance with it, Allah Says (which means): "And We had certainly sent Nooh to his people, (saying): 'Indeed, I am to you a clear warner, that you not worship except Allah. Indeed, I fear for you the punishment of a painful Day.'" [Quran 11: 25-26]
The noblest of all Prophets and the last of them, Muhammad bin ‘Abdullaah (who was sent with the greatest, most complete and comprehensive message), began with what all the Prophets, may Allah exalt their mention, started their Da’wah (call) -- calling to the 'Aqeedah (creed) of Tawheed (Oneness of Allah), and calling for all worship to be made purely and sincerely for Allah alone. Allah's Messenger started with the principle: 'Witness that none has the right to be worshipped except Allah.'
Allah Says (what means): "Say, (O Muhammad): 'O mankind, indeed I am the Messenger of Allah to you all, (from him) to Whom belongs the dominion of the heavens and the earth. There is no deity except Him; He gives life and causes death.' So believe in Allah and His Messenger, the unlettered Prophet, who believes in Allah and His words, and follow him that you may be guided." [Quran 7: 158]
The verses in this regard are many, what we quote here is just one example. With regard to the Sunnah (traditions and approved actions of Prophet Muhammad ), there are many clear indications that Allah's Messenger began his call to Islam with Tawheed.
1. `Amr bin Abasah As-Sulami, may Allah be pleased with him, said: "During the times of ignorance … I heard of a man in Makkah who received revelation. So I set upon my riding beast and came to him. At that time he was in hiding, due to the oppression of his people. So I behaved in a way that enabled me to gain access to him in Makkah. I said to him: "Who are you?" He replied: "I am a Prophet.' So I said: "And what is a Prophet?' He said: 'Allah has sent me as a Messenger.' So I said: 'And what is it that He has sent you with?' He said: 'I have been sent to order the joining of ties of relationship, to break the idols, so that Allah is worshipped Alone and nothing at all is associated in worship along with Him." [Muslim]
2. At the time of the peace of Hudaibiyyah, Hiraql (Heraclius) asked Abu Sufyaan some questions about Allah's Messenger, among which he asked: "What does he (Muhammad) command you?" Abu Sufyaan replied: "He says, 'Worship Allah Alone and do not worship anything else along with Him, and abandon what your fathers say. He also orders prayers, charity, and the joining of the ties of relationship.'" [Al-Bukhari]
Consequently, the Prophets, may Allah exalt their mention, did not come to bring about the downfall of one State to replace it with another. They did not seek sovereignty, nor did they organize political parties for this reason. Rather, they came for the guidance of humankind, to save it from misguidance and Shirk (polytheism), and to take them out of darkness into light.
In this regard Prophet Muhammad gave an example about himself. He said: "The similitude of me and the message with which Allah has sent me, is like a man who came to some people and said: ‘I have seen the enemy forces with my own eyes and I am a mere warner (to you). So, save yourselves, save yourselves!’ A group of his people obeyed him and went out at night, slowly and steadily and was safe; while another group belied him and stayed in their place until the morning when the army destroyed them. Such is the similitude of those who obey me and follow what I have brought (i.e., Message) and of those who disobey me and belie the Truth which I have brought." [Al-Bukhari, Muslim and others]
The Message of the Messengers, by the Mercy of Allah, revives and enlightens the believer’s soul. This enlightenment is the revelation of Allah, which leads mankind from the darkness of Shirk (polytheism) and ignorance to the Light of Truth and Islam: "Allah is the ally of those who believe. He brings them out from darkness into the light." [Quran 2: 257]
The Messenger and the Message are evidence against the disbelievers
Allah sent His Messengers and His Books so that there can be no excuse for mankind on the Day of Judgment. The Quran says (what means): "(we sent) Messengers as bringers of good tidings and warners so that mankind will have no argument against Allah after Messengers." [Quran 4: 165]
The Message of Allah deals with the rights of Allah on His bondsmen, the rights of man on His Creator, The Oneness of Allah and its influence on the creation, knowledge, admonition, the wisdom behind the creation, righteousness, mutual interactions, refutation of incorrect beliefs and deviations, lawful and unlawful, migration and Jihaad. In totality, it is the complete code for righteous living, which results in delight, pleasure and harmony in this life and the Hereafter.