Matthew  27:3-8

      
       When Judas, the traitor, learned that Jesus had been condemned, he repented and took back the thirty silver coins to the chief priests and the elders.  “I have sinned by betraying an innocent man to death!” he said.  “What do we care about that?”  They answered.   “That is your business!” 

       Judas threw the coins down in the Temple and left then he went of and hanged himself. 

       The chief priests picked up the coins and said, “This is blood money, and it is against our Law to put it in the Temple treasury.”  After reaching an agreement about it, they used the coins to buy 'Potter’s Field', as a cemetery for foreigners. 

That is why that field is called
“Field of Blood” to this very day.