What is the ruling on cupping (hijama)? Is it a Sunnah? Does it have specific times? Is donating blood a substitute for it? And what are its benefits?

Cupping (Al-Hijamah) is permissible and is considered one of the legitimate and important methods of treatment. The Prophet, peace and blessings be upon him, underwent cupping and guided his community to treat themselves with it. It is preferable for cupping to be performed on the seventeenth, nineteenth, or twenty-first day, based on the Prophet's saying, peace and blessings be upon him: "Whoever performs cupping on the seventeenth, nineteenth, or twenty-first day, it will be a cure for every disease." As for blood donation, there is no text indicating that it can substitute for cupping. It is advisable to consult specialists regarding this matter.