Blood Money (Ad-Diyat)
Bukhari :: Book 9 :: Volume 83 :: Hadith 10
Narrated Anas bin Malik:
The Prophet said, "The biggest of Al-Kaba'ir (the great sins) are (1) to join others as partners in worship with Allah, (2) to murder a human being, (3) to be undutiful to one's parents (4) and to make a false statement," or said, "to give a false witness."