It is unfortunate that the idea that God is our Father has become a cliché. It has been watered down to a vague, sentimental idea that we are all God’s children and should act like it. This is not the Biblical idea, and it takes the punch out of a highly shocking concept. The idea of God for many faiths is that of a high and holy God who is harsh and unapproachable. And Biblically there is an element of truth in this. God does require moral perfection (Isaiah 6:1-5; 1 Peter 1:14-17; Matthew 5:48). But we are sinners and unable to live up to this standard (Romans 3:23; Jeremiah 17:9; Isaiah 64:6). This is the point of the gospel, that a holy God could take condemned rebels hostile to Him and make them into His children. This should not be watered down into a vague indulgence which would not dream of criticizing us for anything we do. But rather, it is God reaching across the divide between us to make a way for us to come to Him.
Christ on the cross paid the price for all our sin (1 Peter 1:18; Colossians 2:13,14; 2 Corinthians 5:21) and offers forgiveness based on faith in Him (Romans 4:4-8; Ephesians 2:8,9; Philippians 3:9). The result of this is that we become God’s children (John 1:12,13; Ephesians 1:5; 1 Peter 1:23). This is not something that is true of everyone or that can simply be taken for granted (John 8:42-44; 1 John 3:10; 5:4,5). Rather, it is the description of those who have been reconciled to God through Christ.
This results in a new relationship, one not of a servant but a child (Galatians 4:4-6; Romans 8:15; John 8:32-36). And if a child, then an heir of the riches of God (Galatians 4:7; Romans 8:16,17; Titus 3:7). And if God loved us enough to send Christ to die for us when we were His enemies (Romans 5:6-8; John 3:16-18; 1 John 4:9,10), how much more will He love us now that we are His children (Romans 5:9,10; 8:31-39; John 15:15). Therefore, we can face life knowing we have a Heavenly Father who cares for us (Matthew 6:9-13; 7:7-11; Luke 18:6,7). Now this should affect the way we live, because as God’s children, we are being transformed into the image of Christ (2 Corinthians 3:18; Romans 8:29-30; 1 John 3:2). If then we are children of God, other believers are part of our family, and we need to love them (1 John 3:14-18; 4:20,21; 1 Peter 1:22). For being a child of God is not a vague truism, but a transforming reality for those who put their faith in Christ.