Matthew 27:8

Wherefore that field was called, The field of blood, unto this day.

The field in question was purchased with the silver pieces Judas gave back after betraying Jesus. It was set apart as a public burial place for strangers. It was called the Field of Blood because the money that bought it was the price of blood, paid for Jesus' betrayal and death. That name continued in use unto this day, still current at the time the Gospel was written.

The purchase and the disposal of the silver fulfilled the prophecy concerning the thirty pieces of silver being cast to the potter in the house of the Lord. The verse belongs to the account of Judas' death after the betrayal, when having hanged himself he was found dead beneath the tree with his body mangled. His remains were buried. His dead body is set alongside those guilty of Jesus' blood, whose fearful faces showed they felt retribution was already coming upon them.