What is the ruling on saying: "The Prophet's name protects him" or "The Prophet protects him"? And is this saying forbidden even if one does not intend to attribute protection to the Prophet, may God's prayers and peace be upon him?

The saying: "The Prophet's name is his guardian and protector" is polytheistic (shirk) because it attributes benefit and harm to other than Allah, even if the one to whom it is attributed is the Messenger of Allah, peace and blessings be upon him. For he possesses no power to harm or benefit himself or others. If one believes that the Prophet's name can benefit or harm independently of Allah, then it is major shirk (associating partners with Allah). If one believes that it is merely a cause, then it is minor shirk. If one is ignorant of the ruling, they may be excused, but they might still be sinful due to their negligence in seeking knowledge. It is forbidden even if one does not intend to attribute guardianship to the Prophet, because the phrase bears no other meaning, and it must be prohibited.