Romans 9:24-26 meaning

Paul references the book of Hosea from the Old Testament to prove his point in these verses that God calls His people from both Israel as well as from among the Gentiles. 

The prophet Hosea was commanded by God to marry and stay with an unfaithful woman (a prostitute). God commanded Hosea to give his children symbolic names. Hosea named one of his children "Lo-Ammi" ("Not My People") and another of his children "Lo-Ruhamah" ("Not my beloved"). The book of Hosea represents God's desire to restore His people, and while Gentiles are not of the ethnic heritage of God's people, God adopted them through Jesus's sacrifice. 

Paul is using this passage from Hosea to reiterate that those who were not God's people (Gentiles) can now be a part of God's people through faith in His son: Even us, whom He also called, not from among Jews only, but also from among Gentiles (v 24). 

Verse 24 demonstrates this, as Paul says that it is not only Jews who have been pre-planned for mercy to display God's glory (v 23), but also the Gentiles. Paul quotes directly from Hosea. 

As He says also in Hosea, "I will call those who were not My people, 'My people,' 

And her who was not beloved, 'beloved.'" 

"And it shall be that in the place where it was said to them, 'you are not My people,' There they shall be called sons of the living God" (vv 25-26).

Paul is telling the audience in Rome that it is not only the Jews whom God has called to be His people, but that some Gentiles will also be adopted into God's people through faith in Jesus's sacrifice. God has called them directly, so they do not have to come to Him through adopting Jewish religious customs. 

As we will see in verses 30 through 33, God has called some Gentiles to righteousness through faith to make them vessels of mercy for His glory (v 23). In verse 26, Paul is emphasizing that some Gentiles have been called by God to be His children.