Indeed all praise is for Allaah, we praise Him, we ask for His help, and for His forgiveness. We seek Allaah's refuge from the evils of ourselves and from our evil actions. Whomever Allaah guides, then none can lead him astray, and whomever Allaah misguides, then none can guide him. I testify that none has the right to be worshipped except Allaah, alone, having no partner, and I testify that Muhammad is His Slave and His Messenger. He sent him with guidance and the true religion, that he should make it manifest and victorious over all religions, even though the disbelievers hate that.
A number of matters led me to write about this matter, the most important of them being:
Firstly, the ummah of Islaam is in a state of disagreement and divergence in many different areas, both with regard to 'aqeedah and other matters besides, and they have taken divergent paths. Then a number of calamities have befallen them as a result of this divergence, due to the fact that in matters of disagreement they do not refer back for their resolution to the Book of their Lord and the Sunnah of their Prophet. The true extent and seriousness of these calamities is known only to Allaah - the splits in their ranks, the blazing fires of disputes and arguments between them, then the subjugation of the lands of Islaam by the enemies, and their (the disbelievers) desecration of their abodes, their enslavement and the humiliatiopn of the Muslims.
Secondly, the appearance of ideologies in the Islamic field having their own particular programmes and methodologies to rescue and rectify the condition of the ummah. Some are political, some are intellectual, some are spiritual. The followers of each of these ideologies claim that their ideology is the true methodology of Islaam which must be followed and which can alone save the ummah.
These two reasons, along with others, prompted me to carry out one of the greatest and most important obligations: explaining the methodology of the Prophets in calling to Allaah, in light of the Book and the Sunnah, and to explain the characteristics which are particular to it, and to make clear the neccessity of following it alone, since it is the sole way leading to Allaah, which earns His Pleasure, and it is the sole way to rescue the ummah and to attain ascendancy and nobility on this earth and happiness in the Hereafter.
Then, Allaah, the Most High, the Creator, the One who brought everything into existence, the One who formed and fashioned everything, the All-Knowing, the All-Wise, created this tremendous creation and regulated it and ordered it, with His all-encompassing knowledge, His perfect wisdom and comprehensive power, and this was for very great and wise purposes, and lofty and noble goals, far removed from mere amusement, futility or play. Allaah, the Most High, says,
"We did not create the heavens and the earth and all that is between them in play. We did not create them except for a true and wise purpose (to test and examine who are obedient, and to reward them, and who are disobedient and punish them), but most of them do not know." 
Allaah, the Most High, says,
"Haa Meem. This Book (the Qur'aan) is sent down by Allaah, the All-Mighty, the All-Wise. We did not create the heavens and the earth and all that is between them except for a true and wise purpose, and for an appointed term. But those who disbelieve turn away heedlessly from the warning given to them." 
So He created the jinn and mankind and made clear the very great and wise purpose and noble goal for which He created them. He, the Most High, says,
"I did not create jinns and mankind except that they should worship Me. I do not seek provision from them, nor do I seek that they should feed themselves or the creation. Verily it is Allaah Who is the sole Provider, the All-Powerful." 
Allaah, the Most High, says,
"Do you think that We created you in play and that you would not be brought back to Us? High and exalted is Allaah, the True King, above what the idolaters associate with Him. None has the right to be worshipped but Him, the Lord of the Glorious Throne." 
He, the Most High, says,
"Does the disbeliever think that he will be left unaccountable, without being punished for disobeying the orders and prohibitions of his Lord?" 
He, the Most High, says,
"Exalted is He in whose Hand is the dominion of everything, and He is able to do all things. He who created death and life to test who is the best and most obedient in action, and He is All-Mighty (who severely punishes those who are disobedient), the Oft-Forgiving (who forgives those who turn in repentance to Him)." 
So Allaah, the Most High, informs that He createdbthem only to test them, for it to be made clear which off them is best in action, by their submitting and complying to the way of Allaah and following the Messengers of Allaah. And Allaah, the Most High, says,
"O mankind, single out your Lord with worship; He who created you and all those who came before you so that you may be of those who seek to avoid Allaah's punishment and Anger, those whom Allaah is pleased with. He Who has made the earth a resting place for you and has made the sky a canopy, and sent down rain from the sky, and brought out with it crops and fruits from the earth as provision for you. So do not set up rivals with Allaah in your worship whilst you know that you have no Lord besides Him." 
So He ordered them to fulfil the goal for which they were created. He also explains that He was made available to them every means which will help them to fulfil their great task, and He warned them against deviating from this goal and denying these great blessings:
"So do not set up rivals with Allaah in your worship whilst you know that you have no Lord besides Him." 
Furthermore, Allaah, the Most High, says:
"We have indeed honoured the children of Aadam and have carried them throughout the land (upon riding beasts) and the sea (upon ships), and have provided them with good and pure sustenance, and have given them excellence over many of those whom We created." 
Allaah did not give mankind this honour, excellence and high station except due to the importance of the goal for which they were created, which is the worship of Allaah, alone, and to glorify Him and to declare His being exalted and far removed from all defects and from having any partners or rivals, and High is Allaah and far removed from any such thing. So Allaah often mentions the honour and excellence given to mankind and his standing within the creation, and that the other creatures have been subjected to him for his ease and welfare, so that he should fulfil his duty and carry out the purpose for which he was created in the best and most complete manner. Allaah, the Most High, says,
"Say, O Muhammad, to My slaves who have believed, that they should establish the obligatory prayers perfectly, and spend in charity from the sustenance We have provided for them, secretly and openly, before the coming of the Day of Resurrection when there will be no bargaining and no befriending. Allaah it is Who created the heavens and the earth from nothing, and He sends rain down from the sky and produces fruit and crops with it as a provision for you. He has caused ships to be at your disposal so that you may travel upon the sea (and carry provision from land to land) by His permission and He made the rivers to be of benefit to you. Furthermore, He made the sun and the moon to follow one another, constantly pursuing their courses, to be of benefit to you, and He made the night and the day to be of service to you. And He provided for you from all those things which you require, and if you were to count the blessings of Allaah upon you, then you would not be able to enumerate them (nor to give thanks for them). Indeed those of mankind who deny Allaah's favours, and attribute worship or thanks for the favours to other than Him, are great wrongdoers and extreme in ingratitude." 
 Soorah ad-Dukhaan (44):38-39.
 Soorah al-Ahqaaf (46):1-3.
 Soorah adh-Dhaariyaat (51):56-58.
 Soorah al-Mu'minoon (23):115-116.
 Soorah al-Qiyaamah (75):36.
 Soorah al-Mulk (67):1-2.
 Soorah al-Baqarah (2):21-22.
 Soorah al-Baqarah (2):22.
 Soorah al-Israa (17):70.
 Soorah Ibraaheem (14):31-34.