Early Christians like Polycarp were martyred because they refused to confess Caesar as lord. They knew that Jesus alone is divine and would have no one usurp His status. These Christians knew the New Testament is not merely being polite when it calls Jesus “Lord”; rather, it is teaching that Jesus is God Almighty. Idols of sex, money, power, prestige, and so on can become lords if we are not careful; therefore, let us always confess that Jesus Christ alone is Lord.
For further study:
The Bible in a year: