The events from 11:27–12:44 happen in the temple (see 11:27; 13:1). This story, or parable, is closely connected to the earlier question about the authority of Jesus (11:27–33). Mark introduces it with the words, "Then Jesus began to speak to them." The parable is the extended answer Jesus gives to the religious leaders.
Jesus wanted his audience to understand this parable in the context of Isaiah 5:1–7. This tells a similar story about planting a vineyard, building a lookout tower, putting up a fence, and digging a pit for a wine vat. Both stories also ask a similar question about what the owner will do next (Mark 12:9; compare Isaiah 5:4). In Isaiah, the vineyard clearly represents the people of Israel (Isaiah 5:7). In the same way, people hearing the parable would understand it as a story about Israel.
Several parts of the parable have symbolic meaning:
The tenants represent Israel’s leaders.
The owner represents God.
The servants represent the Old Testament prophets.
The beloved son represents Jesus, the Son of God.
The murder of the son points to the crucifixion of Jesus.
The vineyard being given to others points to the judgment that would come upon Israel (Mark 11:15–17; 13:1–37).
Mark's audience would understand this explanation more clearly than the original audience hearing the words of Jesus. Even so, the religious leaders understood enough to realize that Jesus was speaking against them, and they began looking for a way to kill him (12:12).