Matthew 20:21

The request evidently grew out of what Jesus had said about the Son of Man sitting on His throne of glory and the disciples judging the 12 tribes of Israel (Matthew 19:28). The right and left hand positions alongside Jesus suggest positions of prestige and power in His kingdom. Note that the disciples viewed the messianic kingdom as still future. The fact that they would make this request shortly after Jesus had again announced His death shows how little they understood about His death preceding the establishment of the kingdom. They did not understand the need for the Cross much less Jesus’ resurrection, ascension, and an inter-advent period.