What is the grade of the Hadith: "No scratch from a stick, no stumble of a foot, and no twitching of a vein befalls a man except due to a sin, and what Allah forgives is greater"? And does it indicate that everything that befalls a person is due to his sins, given that it was not found in "Sahih al-Bukhari" and "Fath al-Bari" after reading it in "Tafsir al-Qurtubi"?

The aforementioned Hadith (definition) has a weak chain of narration, but its meaning is sound and supported by other evidence from the Quran and Sunnah (definition). Indeed, calamities may occur due to a sin, serving as an expiation for it, as affirmed by His (the Most High) saying: "And whatever strikes you of disaster - it is for what your hands have earned" and His saying: "Whatever good befalls you is from Allah, and whatever evil befalls you is from yourself." Furthermore, calamities elevate ranks and expiate misdeeds, as stated in authentic Ahadith narrated by Aisha (may Allah be pleased with her), which necessitates being content with them.