Is it permissible for a committed Muslim who suffers from a mood disorder to smoke two or three cigarettes of the lightest types daily, taking care that no one sees him, on the grounds that it benefits him psychologically, and with his full knowledge of the ruling on smoking?

Smoking is forbidden, and it is impermissible to seek medical treatment with it, based on the hadith: "Do not seek treatment with unlawful things," and the Prophet's (peace be upon him) saying: "Indeed, Allah has not made the cure for my nation in what He has forbidden to them." Thus, treating with forbidden things is reprehensible both legally and rationally. Allah has forbidden them due to their impurity, and prohibition necessitates avoiding them. It is not permissible to use them as medicine, just as what is forbidden imparts a characteristic of impurity to one's nature and soul.