Summary: The disciples had to learn, often the hard way, that following Jesus does not mean favoritism from Him. They had to learn that service towards God and others is to be done with a loving, gracious attitude and not with an ego.
You have to admit that James and John thought a lot about their ability to serve the Lord Jesus. They wanted places of honor in the Kingdom of God without coming to grips with the hardship that follows everyone who gives their lives to Him. The disciples and all who would surrender their lives to the Lordship and saving grace of Jesus over the centuries would experience not glamor, but grief, and not power, but persecution (2 Timothy 3:12). These two "sons of thunder" were blatant examples of self-exaltation, which was the very poison that Lucifer and the fallen angels possessed (Isaiah 14:13-14) which will end in eternal doom for them (Matthew 25:41) in everlasting hell. We all think far too highly of ourselves and often get on our respective "high horse", making the mistake of looking down on everyone else and believe that we are more important to the cause of the Kingdom than others.
We think that our words are so eloquent and our actions so noble when the hard truth is that save for the mercy and grace of God through Jesus Christ, we are all hell-bound sinners absent of any hope, and it is high time that we look at ourselves through that perspective (Romans 3:10-18, 23). We tend to worship at the altar we have built and dedicated to self-reliance and esteem, believing that we are not as "bad" as the person living next door who has had one too many shots of whiskey that weekend or other situations that blur reality. We pride ourselves on the collection of morals and ethics we have formed in our own image at the expense of seeking the face of God and learn from Him as to what it means to have a genuine righteous lifestyle (John 17:17; 2 Timothy 3:15-17; Hebrews 4:12; 2 Peter 1:19-21).
Scripture does not spare feelings nor apologize for its direct hit at the souls and sins of reprobate humanity, pointing out that we are hopeless, helpless, and doomed unless we repent, ask for forgiveness of our sins, and bow before the Lord Jesus, surrendering our lives to His will (Philippians 2:5-11). Scripture and its truth stand firm and unbending when the emotional bellowing of the wicked reaches its peak and then fails. Any desire to exalt our feelings and opinions before the holiness of Almighty GOD is fruitless and a waste of time. The Word of God shows that the worship of self at the expense of service to Him never ends well for us; yet we never seem to want to learn our lessons.
Moses himself got a case of the "big head" when he claimed to be the source of water for the ever-complaining Israelites in the wilderness (Numbers 20:8-12) and as a result of this foolish statement, God would not allow him to enter the Promised Land. Moses was receiving the credit and benevolence toward Israel that belonged solely to God. Today we are not to think too highly of ourselves in front of notable individuals or important figures and I can think of no better example from my years of service to the Lord Jesus than my peers in seminary who were considerably younger than I was, and some tended to think that their preaching and character made them a sure heir of men such as the late Dr. Billy Graham and noted pastors and leaders within my respective denomination. Some made the mistake of wanting to "name-drop" in order to appear more dignified. They needed to get back to the Word of God and read what none other than King Solomon said about folks such as them (Proverbs 25:6-7, 27:2).
It is not just individuals who serve themselves a large helping of self-esteem and egotism disguised as noble intentions. Ancient empires such as Babylon which overran and conquered the kingdom of Judah in fulfillment of the warnings from God's prophets, had their time in the sun. God in HIs decree allowed them to be used to fulfill His will. Babylon was steeped in paganism and did not regard the LORD, save for Nebuchadnezzar II who was humbled by Him and had been warned by Daniel. They believed that their kingdom would last for eons, but later fell to the Persians in 532 B.C. (Daniel 5). The prophet Isaiah had spoken of Babylon's rise and fall (Isaiah 47:8-11). This is a stern warning for any nation that dares to rebel against the rule of the LORD. No one gets away with anything. God sees all of it and He will demand accountability from both people and nations at the last day (Hebrews 9:27).
The Lord Jesus told a parable about a famer who boasted in his goods and believed that all would be well. He placed his trust in himself and his possessions, certain that this life would be all that concerned him. God had a warning and rebuke for this foolish man, and it was not pleasant in terms of his eternal soul and destiny (Luke 12:13-21). Jesus also told a parable of two men who went to pray in the Temple; one a Pharisee whose prayer was a list of self-achievement and religious pride, and a tax collector who saw himself as a sinner in need of mercy from God (Luke 18:9-14). Which prayer did the LORD hear and honor? Which role best describes you when you go before the LORD to pray? Which role best describes your attitude towards serving the LORD?