Paul called himself a slave or “servant”(δοῦλος/g1401) of Jesus Christ. Some scholars think that he wanted people to think about Joshua, Moses, and Jonah, who were also called “servants.” More scholars think that Paul was a servant because he wanted to obey and serve God.
The Bible prophesied that the Messiah would be a descendant of King David (see: 2 Samuel 7:12-16; Isaiah 11:1; Jeremiah 23:5-6). Jesus was a descendant of David (see: Matthew 1:1-17; Luke 3:23-38).
Paul wrote about the spirit of holiness. Some scholars think Paul was speaking about the Holy Spirit (see: Isaiah 63:10). Other scholars state that it referred to the holiness Christians have (see: 2 Corinthians 7:1; 1 Thessalonians 3:11-13).
Paul wrote “received grace and apostleship.” Some scholars he was talking about all Christians. Christians received grace in the same way that Paul did. Other scholars think Paul spoke about the other apostles who, like him, were called by Jesus.
When God’s people insisted that they were telling the truth, they sometimes said that God was a witness of the things they said. This was a type of oath.
Some scholars think that in his “spirit” meant that Paul completely served God. Other scholars think he was speaking serving God with the power of the Holy Spirit.
Gentiles were any non-Jewish people. Many Gentiles were also “Greeks,” because they spoke Greek. “Foreigners” were Gentile people who could not speak Greek (see: 1 Corinthians 14:11).
A “debtor”(ὀφειλέτης/g3781) was someone who owe something to someone (see: Romans 15:27). This was often money. God wanted him to preach the gospel. Therefore, Paul needed to preach the gospel.
### What was “for the Jew first and for the Gentile”?
Paul said that salvation came to the Jews first. He wanted to know that Jesus began to tell Jewish people how to be at peace with God before he began telling the Gentiles how to have peace with God. He did this after the Jews rejected their messiah.
Paul spoke about God’s “righteousness.” Some scholars think Paul wanted to say that God is righteous (see: Psalm 50:6; Romans 3:5). Other scholars think Paul was writing about the righteousness that God gave people when he justified them (see: Romans 3:21; 10:3). Other scholars think Paul was writing about salvation (see: Isaiah 51:6).
### How was God’s righteousness “revealed from faith to faith”?
Paul wrote about God’s righteousness revealed from faith to faith. Some scholars think Paul wanted people to know that they were saved because they believe in Jesus. Other scholars think Paul wanted Christians to have more faith or to trust God more. Other scholars think Paul wanted them to the Jews to change what they believed. Before, they needed to believe in God. Now, they also need to believe in Jesus, who is God.
Paul wrote about holding back the truth. This is a metaphor. The evil people tried to stop the truth. They did not destroy the truth, but they did keep it from changing them.
See: 2 Thessalonians 2:10
### What was their “senseless hearts were darkened”?
People with “senseless hearts” could not think in the right way because of their sin.
### What were “natural” and “unnatural” relations?
Paul wrote about natural and unnatural relations. Sex between a husband and a wife were “natural”(φυσικός/g5446). That is, it is the way God intended it to be. Other types of sex were “unnatural”(φύσις/g5449). They are sins and God does not want people to do these things.