Qur'an...
Qur'an, 17:26-27 The Messenger of Allah (S) said: Squandering is to spend even one dirham on what does not benefit you. Is there squandering worse than to spend one’s money on things that are harmful to his health and dangerous to his life? Smoking is also included by this saying of the Messenger of Allah (S): There should be no harm (against oneself) and no harming (against others).
Is there any harm worse than cancer, which has been proven by medicine and sciences of today to affect smokers and do away with their lives? Smoking is proven to cause dyspnea and that the nicotine in cigarettes causes addiction, which a smoker can hardly get rid of. Sociologists in the developed countries knew the dangers of smoking; therefore, smoking was prohibited in the public halls, state centers, airplanes, trains and other means of transport.
Lastly, the British government forbade smoking in the metro and the same was done by the French government. Modern medicine has proved that a smoker, in addition to harming himself, harms others who sit with him in a place or in a vehicle during a journey. Therefore, smokers are forbidden to smoke inside public places and are forced to go out to smoke in the open air if they want to smoke, as a kind of regard for others’ feelings and safety.
This is actually what the (S) meant when he said: There should be no harm (to oneself) and no harming (against others). In fact, in this saying there is a prohibition for smokers not to smoke even if they are alone, because a Muslim is prohibited from harming himself, as he is prohibited from harming others. Do you not see that Islam has prohibited suicide? Islam considers suicide as one of the major sins.
A Muslim is not free to harm even his own body, because his body is a possession of Allah and a Muslim has no right to do anything to his body except that which pleases Allah the Glorified. Nowadays, we hear that the developed countries prohibit drivers from having alcohol while driving their vehicle, because it may cause a fatal accident.
In the same way as they prohibit smokers from smoking in public places because they may harm others, we see them apply the rule of “no harm to others” and they neglect the rule of “no harm to oneself” in accordance with the law of FREEDOM which considers man to be free to do to unto himself whatever he likes, as long as he keeps the condition that he does not harm others.