What does Mark 12:14 mean?
The chief priests and the scribes have sent Pharisees and Herodians to Jesus as spies, "who [pretend] to be sincere" (Luke 20:20). The Pharisees and Herodians dislike each other in every other context, but cooperate to oppose Jesus early on in His ministry (Mark 3:6). Jesus threatens the Pharisees because He rejects their devotion to manmade traditions over the Mosaic law (Mark 7:9–13). The Herodians don't like the thought that Jesus might start a revolution that would threaten their relationship with the Roman rulers.The Pharisees and Herodians ironically flatter Jesus as being impartial. They know from experience that He will not overtly side with either group. But the description is valid. Because Jesus is from Galilee, not Judea, He doesn't have to pay the tax in question. Their statement is ironic because Jesus' answer serves neither of their intended outcomes—taking neither of the sides they wanted Him to claim.
The tax they are asking about is the kensos. It is an annual poll-tax, levied on men regardless of what property they own. Rome established it in AD 6, and the different sects of Judaism reacted to it in different ways. Around the time Jesus amazed the rabbis at the temple with His understanding of Scripture (Luke 2:41–52), some angry Jews revolted against the tax. The rebellion's leaders insisted that paying a tax to Rome undermined God's sovereignty over His chosen people. Now, about thirty years later, Jewish Zealots refuse to pay the tax. Pharisees do pay but wonder if it's "lawful" according to God. Herodians support the Roman government, anyway, and either don't see a conflict in interest or don't care.
The Pharisees and Herodians want to know if Jesus holds similar beliefs to the Zealots. Their preferred outcome of this confrontation would be for Jesus to reject the tax. Then, He can be arrested for rebellion against the Romans (Luke 20:20). The Pharisees would win either way, since if Jesus supports the tax, His popular image as the Messiah, come to rescue the Jews from Roman rule, would be in jeopardy.
Like the similar debate regarding divorce, Jesus goes back to the basics (Mark 10:1–12). It's not about politics or even religion; it's about knowing your place in God and living out of that (Mark 12:17). Centuries before, Jeremiah tried to convince the people of Judah to go into exile in Babylon peacefully—that foreign subjugation was God's will for them at that time (Jeremiah 27). Similarly, Jesus has not come to free the Jews from Rome, or its taxes, but to do the work so their hearts can return to God.