While κυριος could be used culturally as a term of respect or authority, the Apostles specifically used "Lord" (κυριος) to indicate divine authority, reverence, or worship when referring to Jesus or God the Father.The Greek word for Lord is kurios and is a masculine title of respect and nobility, which is why we see many others besides God and Jesus being called the “Lord."
- Property owners are called the "Lord" (Matthew 20:8) kurios is “owner” in the NIV.
- Heads of households are called the "Lord" (Mark 13:35) kuriosis "owner."
- Slave owners were called the "Lord" (Matthew 10:24) kuriosis "master."
- Husbands were called the "Lord" (1 Peter 3:6) kurios is "master" in the NIV.
- A son called his father the "Lord" (Matthew 21:30) kuriosis "sir."
- The Roman Emperor was called the "Lord" (Acts 25:26) kurios is "His Majesty."
- Roman authorities were called the "Lord" (Matthew 27:63) kurios is "sir."
For example, Peter addresses Jesus as "Lord" (κυριος) with the understanding of His divine nature, particularly after Jesus' resurrection (Acts 2:36). Similarly, "Lord"(κυριος) is also used in prayers addressed to God the Father (as in Acts 4:24). The Apostles reserve this title, in its spiritual sense, for the divine alone, and there is no record of them calling any other human "Lord" in the same way as they did for Jesus and the Father.