What does the Bible say about being a true child of God?

According to Romans 8, true children of God are not those simply born of flesh but are defined as the elect whom God chose before the foundation of the world. They are justified through Christ’s righteousness and are identified as those who have experienced the new birth through the Holy Spirit's work. The passage emphasizes that merely being human or a believer in a generic sense does not qualify one as a true child of God; rather, it is through God's sovereign choice and the transformative work of the Spirit that one becomes a true son or daughter of God.