It should go without saying that there is only one Lord. Nonetheless, the trinity doctrine tries to challenge this idea by saying that there are two or three Lords. First, trinitarians will acknowledge that Jesus is Lord (which is wonderful if they would stop there), but they go on to say that “Lord” also refers to “the Triune God” (in which Jesus represents the second of three persons). Sometimes trinitarians additionally say that God the Father is Lord, too. Thus to embrace the trinity doctrine is to embrace two or three Lords, and therefore, be confused about precisely whom we should be seeking to obey.
By contrast, the Bible is clear that there is only one Lord. Both the Old Testament and New Testament explicitly and emphatically make this point (Deuteronomy 6:4; 1 Corinthians 8:6; Ephesians 4;5). God the Father was that Lord until He made Jesus Lord (Acts 2:34-36). Jesus will never cease being Lord (Isaiah 9:7; Daniel 7:14; Ephesians 1:20-21).
Who was God the Father? He was who Jesus was before He became Jesus.
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