What is the ruling on smoking, whether for a beginner or for someone who has been smoking for years and is…

Answer

In the name of Allah, if a competent doctor determines that smoking is harmful, then the person who is accustomed to it must completely refrain from smoking. In fact, we have stated that one who is not yet accustomed to smoking is not permitted to make a habit of it. If addiction occurs and the doctor advises against it, then abstention becomes obligatory. However, if doctors explicitly declare that it is not harmful — hypothetically — then it is permissible for someone already addicted to continue, but initiating the habit remains impermissible. Allah knows best.