James and John were asking for glory without seeing the road that led to it. Only moments before, Jesus had told the twelve that in Jerusalem He would be mocked, scourged, and killed (Mark 10:33-34). Gill says "they had no true notion of Christ's kingdom and glory" and were "dreaming of worldly glory and grandeur." Barnes explains "Ye know not what ye ask" as "You do not know the nature of your request, nor what would be involved in it."

So Jesus asks two questions that turn their eyes from thrones to His cup and His baptism, the suffering just ahead of Him. He does not say "the cup that I shall drink," but "the cup that I drink of." Gill gives two reasons for the present tense: partly because His sorrows had already begun, and partly because what lay ahead was certain.

They answered, "We can" (Mark 10:39). Jesus did not argue with them. He told them, "Ye shall indeed drink of the cup that I drink of; and with the baptism that I am baptized withal shall ye be baptized." But the seats they wanted were "not mine to give; but it shall be given to them for whom it is prepared" (Mark 10:40). When the other ten heard, they "began to be much displeased with James and John" (Mark 10:41). Jesus then called all twelve and taught them that "whosoever of you will be the chiefest, shall be servant of all," because "the Son of man came not to be ministered unto, but to minister, and to give his life a ransom for many" (Mark 10:44-45).

In Scripture, a cup can stand for what God gives a person to go through. Barnes writes, "To drink of a cup, in the Scriptures, often signifies to be afflicted, or to be punished." Jesus used the same picture in Gethsemane: "take away this cup from me" (Mark 14:36). The baptism is a second picture of the same suffering, being plunged into it. Barnes paraphrases the question as asking whether they were able "to endure the trials and pains which shall come upon you."

Matthew's account says the request came through their mother (Matthew 20:20-21). Mark tells it as the brothers' own words. Barnes, commenting on Mark, says, "They did this through the instrumentality of their mother."

In the Greek text behind the KJV (the Textus Receptus), the two questions are joined by kai, "and." Many other Greek texts read e, "or," which is why the ESV says "or to be baptized." Every text includes the baptism question in Mark.

Jesus' question shows that He walked toward the cross knowing exactly what it held, and that He calls His followers to share His road before they share His glory. Mark places this request right after Jesus' plainest prediction of His suffering (Mark 10:33-34). The disciples heard about the cross and still pictured a throne. Matthew Henry observes, "Worldly honour is a glittering thing, with which the eyes of Christ's own disciples have many times been dazzled."

Jesus' promise came true. Barnes points out that "James was slain with the sword by Herod" (Acts 12:2), and that John was banished to Patmos for the testimony of Jesus Christ, where he called himself a "companion in tribulation" (Revelation 1:9). The answer to their request was not a seat but a servant's life, shaped by the One who came "to give his life a ransom for many" (Mark 10:45).