There is no reason why any person, who does not live by the values of religion, and therefore, who is not expecting to be judged by his deeds and ultimately punished, should observe the limits set by God and work for the good and interest of others in order to attain God’s approval. According to his mistaken beliefs, given that he has only one chance to live in this world, he thinks he should lead his life in the most comfortable conditions, go after anything he wants and be able to do anything he likes. In the Qur’an, God puts this rationale as follows:
They say, "There is nothing but our existence in the world. We die and we live and nothing destroys us except for time" They have no knowledge of that. They are only conjecturing. (Surat al-Jathiya: 24)
Anyone with such a mistaken approach is vulnerable to all kinds of wickedness or immorality. He may unabashedly lie, steal, break his promises, resort to violence, take lying for granted, defraud, or exploit the labour and resources of others whenever he has the opportunity. There is simply nothing to hold such a person back from evil.
In time, being enslaved by his ego (lower soul), he obeys its commandments without any hesitation. He sees no limits to how he should engage in wickedness. If it is in his interest, he sees no reason not to commit murder. Daily newspapers run headlines about such incidents. Their pages are full of news about people killing their neighbours for jewellery, women killing their husbands out of rage, fathers torturing their children or people murdering their parents for money. Definitely, there are countless similar incidents occurring each day, which remain hidden. All these provide clear evidence that people have become the blind slaves of their lower selves. Spiritually, they are inferior even to animals. In the Qur’an, each such individual is called "the Transgressor beyond bounds, the Sinner." (Surat al-Mutaffifin: 12)
In a society where people can do anything at any time, an ordinary person next to you in a bus, shopping mall, or theatre, may well pose a potential danger. He may be a robber, a murderer, a rapist. Furthermore, such a dangerous person can be good-looking and have a brilliant educational background.
At such a point, the basic difference between believers and unbelievers becomes most apparent. Whatever the circumstances may be, believers never even contemplate anything condemned by God. The instruction of the Prophet Muhammad (saas) to the believers, "There should be neither harming nor reciprocating harm" (Sunan ibn Majah) also explains this very clearly. Disbelievers, on the other hand, feel free to engage in wicked deeds.
The morals of Islam eradicate from society theft, bribery, lying and murder. One who adheres to the morals of Islam lives by observing the limits of God and does not obey the evil whispered to him by his lower self.
Someone who does not live by the values of religion, on the contrary, always behaves as his own interests demand. This is exactly what leads the way to every kind of wickedness. For instance, stealing may well be in someone’s material interest, but religion prohibits it. As a matter of fact, theft does harm to both the wronged and the wrong-doer. All somebody’s savings can be stolen in a single night, while on the other hand, it may also cause the thief to have "pangs of conscience." For these reasons, religion prohibits such wickedness and opens the way to a beautiful and peaceful environment in this world.
At this point, a disbelieving person may come forward and say: "I do not have faith in God, but neither do I cheat." Indeed, it is quite possible that this person did not cheat throughout his life because of his principles. However, under certain undesirable circumstances, he may not be able to resist temptation and will then cheat other people. For instance, he may be in desperate need of money or he may be in an environment where cheating is considered acceptable. Various other circumstances may lay the appropriate "groundwork" for cheating and thus lead that person into sin.
However, religion strictly prohibits appropriating other people’s property. A person who lives by the principles of religion never attempts to cheat other people. Cheating is a form of injustice which God condemns in many verses:
Do not swallow up one another’s property by false means, nor offer it to the judges as a bribe, trying through crime to knowingly usurp a portion of other people’s possession. (Surat al-Baqara: 188)