"'He had one left to send, a son, whom he loved. He sent him last of all, saying, "They will respect my son." But the tenants said to one another, "This is the heir. Come, let us kill him, and the inheritance will be ours." So they took him and killed him, and threw him out of the vineyard.'" NIV translation
Jesus continues to speak to the religious leaders and told the story of how the owner of the vineyard sent his son to collect what was due. Instead of respecting the owner's authority, as exercised by his son, they killed the son and rejected the owner's rights. According to Jewish law, a piece of land that was not claimed by an heir was sorta up for grabs. They had concluded that the owner was dead and that, by killing the heir, they could claim ownership of the vineyard.