35 Then James and John, the sons of Zebedee, came to Him, saying, “Teacher, we want You to do for us whatever we ask.”
36 And He said to them, “What do you want Me to do for you?”
37 They said to Him, “Grant us that we may sit, one on Your right hand and the other on Your left, in Your glory.”
38 But Jesus said to them, “You do not know what you ask. Are you able to drink the cup that I drink, and be baptized with the baptism that I am baptized with?”
39 They said to Him, “We are able.” So Jesus said to them, “You will indeed drink the cup that I drink, and with the baptism I am baptized with you will be baptized;
40 but to sit on My right hand and on My left is not Mine to give, but it is for those for whom it is prepared.”
Mark 10:35-40, NKJV

The disciples did not understand the kingdom’s true nature. They continued to argue and dispute over which of them would be the greatest. On this occasion, James and John approached Jesus privately and requested that they be given favored positions in His kingdom.

Jesus told them they did not understand what they were asking. He then asked if they could drink the cup that He would drink and be baptized with the baptism with which He would be baptized. He would mention the cup again while praying to the Father in the Garden of Gethsemane (Mark 14:36). Here, the cup referred to the suffering and death of the cross (Luke 12:50). The Greek word for baptism means “to plunge or immerse.” The events of the cross would plunge Jesus into immense suffering.

Though they didn’t understand what Jesus meant, James and John were confident they could share in His cup and baptism. Jesus affirmed they would share in His suffering. James was the first apostle to be martyred when he was executed by Herod (Acts 12:1-2). According to tradition, John was not killed, but he suffered for the cause of Christ (Rev. 1:9).

Although they would share in His cup and baptism (suffering), Jesus told them He was not able to grant their request to be seated on His right and left. This is not a position to which one is appointed; it is one that he earns because of his character, as Jesus would go on to explain.

When the other ten apostles heard about what had happened, they became greatly displeased with James and John (Mark 10:41). Jesus immediately addressed this situation, as it threatened to destroy the unity of the twelve. He reminded them that the rulers of the Gentiles used their power and authority to rule over their subjects. However, it should not be so among them. In God’s kingdom, one achieves greatness, not by exercising power and authority, but by serving others.

Jesus used His own life’s work to illustrate this principle. “For even the Son of Man did not come to be served, but to serve, and to give His life a ransom for many” (Mark 10:45).” Of all people, Jesus was in a position to demand service from others. Instead, He rendered service, even to the point of dying on the cross to secure our salvation. Because of this willingness to sacrifice and take on the role of a servant, God gave Jesus the position of highest honor, power, and authority (Phil. 2:5-11).