Contrary to popular opinion, Jesus was big into politics. Seriously. In fact, Jesus directly challenged the political and religious powers of his day. Those powers were the wealthy ruling classes of Judea; the Sadducees and Pharisees.
Even a cursory read of any of the gospels shows Jesus continually rebuked the Pharisees and Sadducees for their hypocrisy, corruption and twisted interpretations of Hebraic law. Jesus was perceived by the ruling classes as their enemy.
Many times Jesus said things like:
Woe to you, teachers of the law and Pharisees, you hypocrites! You are like whitewashed tombs, which look beautiful on the outside but on the inside are full of the bones of the dead and everything unclean. In the same way, on the outside you appear to people as righteous but on the inside you are full of hypocrisy and wickedness.
The Pharisees and Sadducees tested Jesus:
The Pharisees and Sadducees came to Jesus and tested him by asking him to show them a sign from heaven.
Matthew 16:1 (see also Matthew 22 and Mark 12)
And, they plotted constantly to trick, embarass and get rid of him:
But the Pharisees went out and plotted how they might kill Jesus.
What we have missed is that the Pharisees and Saducees were not just religious leaders. They also were the political leaders of Israel during Jesus' time. [Note: Israel was called Judah at the time; renamed Judea by the Romans.] Judea had been conquered by the Romans and was an occupied territory. However, the Romans did not run everything in Judea; not even close. As long as the Jews paid their taxes and didn't revolt, Rome had little interest in their internal affairs.
For instance, they had their own police (temple guard) and public jail (Acts 5:18). Julian Spriggs says:
It was the normal Roman practice to leave most of the running of the government to local leaders. In Judea, this was the Sanhedrin, dominated by the Sadducees, and ruled by the High Priest. In return for their support for Roman rule, the Sadducees kept their wealth and privileged position secure.
The Sanhedrin was the chief legislative body in Judea and was composed of Sadducees and Pharisees (Acts 23:6). It had political, legislative, judicial and religious functions. Members of the Sanhedrin were the equivalent of the congressmen and senators that represent us today.
The Jewish leaders of Jesus' day were unusually powerful because the Roman Governor of Judea, Pontius Pilate, was particularly weak. At various times in his career he had been outmaneuvered and humiliated by the Jewish leaders. In fact, the Roman Emperor, Tiberius Julius Caesar had rebuked Pilate and threatened to remove him due to complaints from the jewish leaders in Judea.
All of this is punctuated at the trial of Jesus. Jesus was only brought to Pilate because the Jewish leaders were not allowed to impose the death penalty. So, they needed Pilate to do that. The gospel accounts state that Pilate thought Jesus was innocent; knew the charges against him were lies; tried to get the Jewish leaders agree to dismiss the case; and only agreed to Jesus' crucifixion after the Jewish leaders threatened Pilate (tacitly warning him they would complain again to Caesar) by saying:
If you let this man go, you are no friend of Caesar.
So, we see that in most ways, the real political power in Judea, the power that really mattered most in the daily lives of the people, was held by the Jewish political and religious leaders that Jesus challenged. How did Jesus challenge them and their political power structure? In addition to calling them hypocrites and fools, he also threatened the financial source of their power.
Just like today, also in Jesus' day, corruption was rampant in politics and government. The Jewish High Priest Annas was sort of the "godfather" of Judea. He gained his political power the old-fashioned way; by using his wealth to bribe the Roman governors to appoint his cronies (mostly family members) to various positions in the government of Judea.
For instance, Annas got the Roman governor to appoint him High Priest of Judea (the most powerful Jewish position in the land) and later got five of his sons and one son-in-law appointed to the same position. The High Priest of Judea was also the Chairman of the powerful Sanhedrin (discussed above).
How did Annas obtain his wealth? Through another time-honored tradition -- corruption. As High Priest, he (and later his sons and son-in-law) controlled the temple and profited from the exchange of money and the selling of sacrificial animals. When a Jew came to pray at the temple and offer a sacrifice (as all males were required to do during passover) they had to exchange Roman coins (with image of Caesar) for Jewish ones so they could buy "approved" animals to sacrifice. All of this happened in the temple courtyards or in the area surrounding it. The High Priest, and his cronies, controlled all of this and profited handsomely from the exorbitant fees they charged to exchange the money and sell the animals.
Jesus directly challenged the corrupt system when he physically and violently (only time Jesus ever resorted to physical violence), cleansed the temple of those who had made it a "den of thieves" (Matthew 21:13).
There is some dispute as to timing, but it seems that the cleansing of the temple by Jesus happened during the week before his death; now referred to as "Holy Week" by Christians. It was Passover week and typically there was a Roman military parade. The Roman officers would ride on horseback, through the front gate of Jerusalem.
Jesus arrived triumphantly riding into Jerusalem -- on a donkey; the people welcoming him by waving palm branches and crying Hosanna! It seems Jesus was making a point, perhaps mocking the power of the "principalities and powers" of his day.
At the end of the week, the leaders of this corrupt system had the temple guard arrest Jesus and bring him to Annas who sent him to his son-in-law, Caiaphas. Caiaphas, as the official High Priest of Judea at the time, conducted the arraignment of Jesus. The roles of Annas and Caiaphas in the arrest and trial of Jesus are discussed in several gospels, including at John 18:12-27.
So, we see that Jesus was very involved in politics. In fact, there may be nothing Jesus did more (as related in Matthew, Mark, Luke and John) than debate the Sadducees and Pharisees over the practical, "real-world", meaning and application of the jewish Torah. The heart of the Torah was, and is, the first five books of the Christian bible. These are the laws Jesus said he didn't come to abolish, but rather to fulfill (Matthew 5:17).
Crucially, these laws were not just about religion. They also were a civil code or constitution, very much concerned with how the rich treated the poor; with justice and mercy.
Woe to you, teachers of the law and Pharisees, you hypocrites! You give a tenth of your spices—mint, dill and cumin. But you have neglected the more important matters of the law—justice, mercy and faithfulness. You should have practiced the latter, without neglecting the former.
Obviously Jesus is talking here about the moral and legal aspects of God's law dealing with justice and mercy towards other people. Jesus was talking about politics and religion blended together as it was in the Torah. You simply could not separate politics out of the discussion of the law and Jesus didn't.
In fact, when Jesus began his public ministry his first words were these:
The Spirit of the Lord is on me, because he has anointed me to proclaim good news to the poor. He has sent me to proclaim freedom for the prisoners and recovery of sight for the blind, to set the oppressed free, to proclaim the year of the Lord's favor.
And that's exactly what Jesus did. Throughout the gospels we see that Jesus proclaimed good news for the poor; both spiritual and physical. He healed the blind and set the oppressed free. He challenged the political leaders of his day to enforce the important matters of God's law -- justice, mercy, love (others more than self), turning the other cheek, lifting up the oppressed, caring for the sick, giving possessions to the poor, etc.
And, of course we discussed earlier that the one and only time Jesus' white hot anger was visibly displayed was when he violently threw off temple grounds the corrupt money changers, the thieves (as Jesus called them), who were using religion to prey on the poor.
The values Jesus emphasized -- love, compassion, peace, healing, justice, lifting up the poor and oppressed (the "least of these") are the very values that liberals today emphasize. In fact, it's hard to find any political issue at all where Jesus took the conservative side.
If we are honest about what the bible says about Jesus, then we must conclude that Jesus was politically active and that his political agenda and values would be considered very liberal today. That much is obvious. It is what it is. Jesus was (and is) a liberal. This should not be a surprise given everything else we read in the bible about things like justice and treament of the poor.
The only question is our response.  Do we share Jesus' politics?
+1 Gospel Politics