What does the Bible say about being called the children of God?

In Romans 9:25-26, Paul quotes the prophet Hosea, indicating that God will call those who were not considered His people as His children. This signifies a profound transformation for those who once stood outside of God’s mercy and love. By God's sovereign grace, they are redeemed and identified not just as His people but as His beloved children. This calling reflects God's initiative and desire to establish a familial relationship with those He has chosen, thereby adopting them as His own.