Because they asked to sit in the important seats in the coming kingdom, Jesus tells James and John are thinking like the Gentiles. James and John are trying to gain an advantage so that they are more honored than the other disciples.
The gentile rulers “lord it over them” (20:25). The verb translated “lord it over” (κατακυριεύω) refers to having mastery or dominion over another. 1 Peter 5:3 says the elders are to be shepherds of the flock, rather than domineering over their charges. The Greco-Roman world was an honor/shame culture. Any Roman elite pursed his own honor at the expense of everyone else. You did what you needed to do to get ahead of your rivals, just as James and John did by asking for prominent seats when Jesus’s kingdom arrives.
Jesus requires his disciples to completely reverse the pursuit of honor common in the ancient world. Matthew 8:11-12 refers to Pharisees pursuing the best seats at meals and doing things which brought honor to themselves. In that context Jesus reverses the expectation most people had: Jews like the Pharisees would be the first to enter the Kingdom of God and sit at the best table along with Abraham, Isaac, and Jacob. But Jesus says they will not even get into that banquet, but rather they will be left on the outside in the darkness.
In Luke 14:7-11 Jesus reverses the common Greco-Roman and Jewish practice of trying to sit in the best seats at a wedding banquet. It is better, Jesus says, to sit in a humble seat and have the host upgrade you to a better seat than to take a better seat and be sent down to a less honored seat.
If you want to be great in the kingdom of heaven, you must be a servant (Matt 20:26-27). Jesus will say something similar in Matthew 23:11-12, contrasting the attitude his disciples ought to have with the hypocritical Pharisees. Contemporary American Christian culture has the same pursuit of honor like the Greco Roman world. Pastors routinely ask, “How big is your church?” Can you imagine Joel Osteen helping set up the chairs in the fellowship hall? Mowing the church lawn?
Jesus himself is the model for serving one another. The Son of Man came to be a servant and a ransom for many (Matt 20:28). Jesus regularly uses the phrase Son of Man to refer to himself, likely evoking Daniel 7:13-14. The Son of Man is about to arrive in Jerusalem, and many expected him to begin to rule with the authority of the Ancient of Days (and do some serious smiting of those who deserve to be judged).
But Jesus connects the (messianic) Son of Man with the Suffering Servant of Isaiah 53. The son of man is not coming to be served as a conquering king rendering judgment, but as a servant of God who will suffer on behalf of many. Isaiah 53 describes the suffering of the servant of the Lord. The identity of that servant was open to interpretation for Jews in the first century. In Acts 8:30-35 the Ethiopian eunuch asks Philip whether the Isaiah 53 referred to the prophet himself or someone else.
The word ransom also evokes several passages in the Old Testament. In Psalm 49:7–9, “no man can ransom another, or give to God the price of his life.” The noun λύτρον and the verb λυτρόω refer to “deliverance by payment, is used in non-biblical Greek primarily of the manumission of slaves and release of prisoners of war” (Davies and Allison, Matthew, 3:95).
The word is translated either “ransom” or “redeem.” In English, a ransom is a price paid to obtain the release of someone who has been kidnapped (mostly in movies!) But the word in the Hebrew Bible, the Septuagint and the New Testament has the sense of a price paid to obtain a slave, to set them free from their old master and become the possession of a new master.
In Exodus 6:6 the word is sued in the context of God rescuing his people out of their slavery in Egypt, “I will redeem (translating גאל) you with an outstretched arm and with great acts of judgment.” The Hebrew verb as the sense of reclaiming something as one’s own (in this case, Israel is God’s people enslaved by the Egyptians, the Exodus events reclaim them as his own people). Similarly, Exodus 15:13 God has redeemed his people because of his steadfast love. In Romans 6:15-18 Paul uses the metaphor of slavery to describe salvation, we were once slaves obedient to a master (sin), but we have been set free from that service and now are slaves to righteousness.
Many in Second Temple Period Judaism thought Messiah will redeem Israel. Luke 24:21, the two disciples on the road to Emmaus thought Jesus was about to “redeem Israel.” In 1 Maccabees, Judas prays before the battle at Emmaus, evoking the memory of God rescuing his people from Egypt and asking God to act favorably and “crush out enemies” so that “Then all the Gentiles will know that there is one who redeems and saves Israel” (1 Macc 4:11). Psalms of Solomon 8:30 asks the Lord to “turn your mercy upon us and be compassionate” (v. 27) so that the Gentiles do not “devour them as if there were no redeemer.” Psalms of Solomon 9:1 looks back to the Exodus events as when the Lord redeemed them.
Psalms of Solomon 8:30 Do not neglect us, Our God, lest the gentiles devour us as if there were no redeemer.
Psalms of Solomon 9:1 When Israel was taken into exile to a foreign country, when they neglected the Lord, who had redeemed them
Matthew 20:28 anticipates what Jesus is about to do as he arrives in Jerusalem. Although his disciples and the crowds are expecting a messiah who conquers, he will be the suffering servant who defeats the real enemy of humanity, sin and death.