In Matthew 28:18-20, Jesus instructs his apostles to baptise and instruct future disciples. So the practice of baptism is an acknowledgement of the kingship of Jesus. When we engage in the practice of baptism we are stating that we accept his authority. What kind of king is Jesus? Is he like other rulers or is he very different? Here are three statements about his kingship.
First, he is a righteous king. In saying this, we are referring to his character. Jesus is both divine and human. A divine person by definition is righteous, it is an essential aspect of his being. But is Jesus righteous as a man? The answer to that question is that he is. When he was here on earth he lived a fully righteous life without one defect.
Second, he is a resurrected king and in saying this we are referring to his victory over the powerful enemy of death. Jesus died on the cross, but he did not enter death as a victim. Instead he entered death as a conqueror and he defeated it by showing that it could not force him to remain there. He rose again on the third day in order to become king.
Third, he is a redeeming king and this is a reference to his intentions. Redemption is a word taken from the slave market and describes the purchase of a slave from an owner. On the cross, Jesus paid the price that was necessary in order for us as slaves to sin to be set free.
In baptism, we are admitting that we are unrighteous, subject to death and in need of liberation from the power of sin. Baptism reminds us that by faith in our great king we can experience his blessings delivered to us by his power. His righteousness becomes ours, his victory over death becomes ours, and his redemption payment sets us free from the dominion of sin.