People may do an action but in their mind it is not necessary that they have the same desire. An action is led by the mind but born by a desire of the heart. The mind often works on reasoning and when the ultimate aim is for a personal gain then the mind could choose the power of darkness to lead; however when the ultimate aim is for the benefit of others the mind chooses to follow the power of the Light. The desire of a heart depends on the condition of the heart. A heart of flesh wishes to achieve what is best for others while a heart of stone aims to empower itself. When the mind follows the power of darkness the heart of flesh raises its voices in the hope that the mind will change its course of action. In case the mind determines to follow its own way the voice of the heart will not be at rest but it continues to raise its voices and this is known as the voice of one's conscience. But if the mind continues to pursue its own way; the voice of the conscience is weakened but not dead.
Representing for the power of darkness and the heart of stone is King Herod because his ultimate aim was to destroy the infant King for his personal gain. He lived in fear of losing his throne and his kingdom would be destroyed by the infant King. His fear was baseless and the fear took over his mind and heart and his action was led by the fear that led to the killing of the innocents. He lied to the Magi who honestly came to him for consultation. He paid lip service to the infant King but his heart was far from Him. His words spoke of loving the infant King but deep in his heart was hatred and loathing. He lived in darkness with a heart of stone. That heart decided to destroy children of the land.
Representing for the power of the Light with hearts of flesh were the Magi because their purpose was to find the infant King to pay homage. They lived in peace and joy and hope and their path was led by the Star in the sky. They left their thrones behind in search of the infant King and had no fear of losing their kingdom. The Magi went in search for the infant King in order to give but they received much more than they gave. King Herod wanted to hear from the Magi to know the whereabouts of the infant King but the Magi went home in different direction. We have no idea where their kingdoms were but we know that they came from afar, well prepared with good intensions and honest, looking for the infant King and after the visit they went home guided from on high. They represent people who are genuinely searching for the Light, the Truth and eternal life.
All kings search for the infant King but their purpose was different. The ones who follow the way of the heart of flesh are satisfied while those like King Herod follow the way of the mind are ultimately disappointed. God is the Supreme Master of all affairs.