As everybody can clearly understand from the Holy Quran and the traditions of Islam, an important purpose behind the mission of the prophets, especially the Last Holy Prophet Muhammad (S), is to guide people to the reformation of their morality and the purification of their souls; that is to say, to make them grow through commands and rules which guarantee their felicity and happiness in this world and the world to come, and to protect them against wickedness, psychological difficulties and ill-treatment.
Allah the Most High said: “Even as We have sent to you an Apostle from among yourselves who recites to you Our communications, and purifies you and teaches you the book and the wisdom, and teaches you that which you did not know.” (2:151)
He also said: “Certainly Allah conferred a benefit upon the believers when He raised an Apostle from among themselves, reciting to them His communications, and purifying them and teaching them the book and wisdom, surely before that they are in manifest error.”(3:164)
The Holy Prophet Muhammad (S) said: “I was not sent but to perfect good behaviour.”
He (S) also said: “Keep on practicing good ethics; because, for such Allah has sent me.”
Imam Ali the Commander of the Faithful (a.s.) said: “O people! When Allah created men, He wanted them to obtain valuable qualities and noble behaviour. He knew that it could not happen except by explaining what is good and what is bad; which in actuality He has explained through religious commands and prohibitions.”