An excerpt from "What Christians Want To Know.com" entitled, "Who Are Children Of God: A Bible Study" by Dr. Michael L. Williams, states: "Some people can look and act like a child of God, but what makes them a child of God is different than what most people believe. The Bible tells us about being a child of God in Galatians 3:26: “For ye are all the children of God by faith in Christ Jesus.” We see that it is faith in Jesus Christ that makes us children of God. God tells us that when we have faith in Jesus Christ, we also become the children of Abraham. As the children of God and Abraham, we are heirs of the promises that God made to Abraham and his children (Galatians 3:6-9; Galatians 3:29-4:6). The Bible says that whoever believes that Jesus is the Christ is born of God (1 John 5:1). If we are born of God (born again), then that makes God our Father (1 Thessalonians 1:1-3) and we are His children as sons and daughters (1 John 3:1).
Read more: https://www.whatchristianswanttoknow.com/who-are-the-children-of-god-a-bible-study/#ixzz8Mu6G8FNB
Reference: 1 Corinthians 9:1