Targum Pseudo-Jonathan on (Genesis 4:11) continues the image. "Now because thou hast killed him, thou art cursed from the earth, which hath opened the mouth, and received the bloods of thy brother from thy hand."
The earth, which was already cursed after Adam's sin for staying silent, now becomes a direct witness in the crime. It opened its mouth — a strange and vivid image — to receive the blood Cain spilled. And for that, the earth itself becomes a courtroom for the curse that follows. Cain will find that the very soil that drank his brother's blood will refuse to yield crops for him.