The significance of 'Umar's description of the witness as 'Sal' al-'Uqab' (The Excrement of the Eagle).

Primary text

The statement by 'Umar, 'O Sal' al-'Uqab,' signifies that the person resembles the excrement of an eagle, which burns whatever it touches. This analogy implies that the penalty must inevitably fall upon one of the two parties: if the testimony is completed, the accused receives the prescribed punishment; if it is not completed, the accusers receive the prescribed punishment (hadd).