Final answer:
The Pharisees plotted against Jesus because they saw his teachings and actions as a threat to their authority, resulting in his arrest and crucifixion by the Romans.
Step-by-step explanation:
The Pharisees plotted against Jesus because they saw him as a threat to their authority and the social order. According to the gospels, the Pharisees, who were a religious and political group within Judaism, disapproved of Jesus's teachings and actions, which often contradicted their interpretation of the laws of Moses and challenged their influence among the people of Palestine. Jesus's message of forgiveness and redemption, as well as his association with individuals they deemed sinners, led to significant tension between him and the Pharisees. Consequently, the Pharisees, alongside other Jewish leaders, conspired to arrest Jesus and bring him before the Roman authorities, accusing him of inciting rebellion and blaspheming against Jewish law, eventually leading to his crucifixion by the Romans.