What is the ruling on smoking, on one who quit it then returned to it, and on one who buys it to offer it to guests?

The ruling on smoking is that it is forbidden due to its harm and foulness. As for offering it to others, it is not permissible because it involves cooperation in sin and aggression and inflicting harm upon others, in accordance with the Almighty's saying: "And cooperate in righteousness and piety, but do not cooperate in sin and aggression," and according to the Prophet's (PBUH) saying: "There should be no harm nor reciprocating harm."