Religion is thinking our good deeds will please God and He will reward us for doing them. Relativism is thinking Christ died for our sins, we are saved and that is all that is necessary. The former could be seen as a focus on Jesus as Lord; the latter as a focus on Jesus as Savior.
However, when Peter preached to his people, he said, “Let all the house of Israel therefore know for certain that God has made him both Lord and Christ, this Jesus whom you crucified.” (Acts 2:36)
He is Lord because He conquered sin and death. He is Lord because He created all things and all things belong to Him. He rules the universe. Whether now or eventually, everyone will bow the knee to Him. We don’t make Him Lord; He is Lord.
He is also Savior because He left His throne to rescue sinners. He died in our place, forgiving sin and granting eternal life to those who believe in Him. We don’t make Him Savior either, for whether people have faith or not, that is who He is.
If I profess faith in Christ, but live as I please, then my god is not the Lord but myself. If I profess faith in Christ, but try to save myself or earn God’s favor by what I do, I am also making a god of myself. Both are putting me over and above what the Gospel says and what Jesus did. I cannot save myself. It is impossible. I cannot live as I please, for if I know Jesus and He lives in me (Gospel), then I must respond in grateful obedience. Faith in Jesus as Savior must include submission to His Lordship.
Even before Jesus came, the nation of Israel struggled with this duel idea of their dependence upon God and their obedience to God. They tried law-keeping but could not keep it up. They lived as they pleased and that didn’t work either. Their error was leaving faith and love for God out of their response to His grace.
When Jesus came and his disciples shared the Gospel with them, “testifying to the kingdom of God and trying to convince them about Jesus both from the Law of Moses and from the Prophets,” some were convinced, but many did not believe.
As they disagreed among themselves, Paul said, “The Holy Spirit was right in saying to your fathers through Isaiah the prophet: ‘Go to this people, and say, “You will indeed hear but never understand, and you will indeed see but never perceive.” For this people’s heart has grown dull, and with their ears they can barely hear, and their eyes they have closed; lest they should see with their eyes and hear with their ears and understand with their heart and turn, and I would heal them.’ Therefore let it be known to you that this salvation of God has been sent to the Gentiles; they will listen.”
After that, he “proclaimed the kingdom of God and taught about the Lord Jesus Christ with all boldness and without hindrance” (Acts 28:23–31) taking the message to the Gentiles who were not so hung up on their religious legalism and lackadaisical relativism.
Perhaps it was this pattern in their history that pushed the early church to focus on the Lordship of Christ. Never again did God want His people to neglect His rule. He had made a promise to them about the coming Messiah saying He would be their King and Lord . . .
For to us a child is born, to us a son is given; and the government shall be upon his shoulder, and his name shall be called Wonderful Counselor, Mighty God, Everlasting Father, Prince of Peace. Of the increase of his government and of peace there will be no end, on the throne of David and over his kingdom, to establish it and to uphold it with justice and with righteousness from this time forth and forevermore. The zeal of the Lord of hosts will do this. (Isaiah 9:6–7)
Yet they didn’t expect a Savior from sin, or a Lord of their lives. They wanted a political ruler who would give them freedom from oppression and allow them comfort and freedom.
As I consider that kind of governing, I cannot think of any king who did that. No leader can rule his subjects without giving them direction, correction, or consequences from their actions. Logic says that before very long, those who lived in that kind of kingdom would soon destroy each other.
Besides logic, the Bible is clear; the kingdom of God under the Lordship of Jesus Christ is totally incompatible with the kingdom of self under the ‘lordship of me.’ Jesus must be (and is) both Savior and Lord.