Jesus told his disciples about who was greatest in the kingdom. There are children born of the law (flesh) and those born of the Spirit (Grace). In God's kingdom, children born of Grace are of higher rank. Those born of the flesh still see wealth and fame and power as being associated with greatness. Those born of the Spirit, however, are servants. John represented the LAW and the prophets while Jesus represented unmerited Grace. Note that at Jesus baptism, John said 'it is I who needs to be baptized by you'.