This article discusses the meaning of Romans 8:15, where Paul speaks of the Holy Spirit as the Spirit of sonship, by whom we cry, "Abba, Father!"

Why did believers in the Old Testament never address God as "Father"? This article looks at the difference of the Old Testament and the New Testament, as well as the importance of the work of Christ in this regard. The author looks at the passages in the Old Testament where it talks about God as Father, and also what it means that Jesus teaches us to call God "our Father" (in prayer).