When the Jews referred to God as a father, they were referring to God’s sovereign authority over their nation. He was the Father to be revered and to be feared when they sinned against him.
Deuteronomy 32:6 Do you thus repay the LORD, you foolish and senseless people? Is not he your Father, who created you, who made you and established you?
Psalm 103:13 As a father shows compassion to his children, so the LORD shows compassion to those who fear him.
Isaiah 63:16 For you are our Father, though Abraham does not know us, and Israel does not acknowledge us; you, O LORD, are our Father, our Redeemer from of old is your name.
Malachi 2:10 Have we not all one Father? Has not one God created us? Why then are we faithless to one another, profaning the covenant of our fathers?

The Jews revered God as their Father through his mighty acts of creation, compassion and redemption. God was known as the One who is superior to Abraham as the living God of his covenant people. In every sense of thinking of God as their Father, the Jewish people understood him to be the transcendent God to be revered. You might note with all of these verses quoted, though God is being described as Israel’s Father, he is not being directly addressed as “Father.” When the Old Covenant people approached their God, they did so only through the access of the temple where God placed his presence and name.

When Jesus came and preached to his disciples, he referred numerous times to their “Father in heaven.” Jesus told his disciples directly that they might approach their Father in prayer by saying, “Our Father…” (Matthew 6:9). I am sure that this would have been a shocking thing for these Jewish disciples to hear. How can we approach this sovereign Creator in such a direct manner? The consideration of this one little phrase of direct address was most probably a jaw dropping moment, but Jesus was sitting right in front of them. He is the fulfilment of the temple and being a disciple of Christ brings direct access to the transcendent God of the universe.

What has changed for the New Covenant people of God? I propose that we first realize what has not changed. God, The Father, is still the transcendent God of the universe. While the Scriptures show that God is both transcendent and immanent, we must not forfeit his transcendence to enjoy his immanence. Both in the Old and New Testaments, God is described in his transcendent holiness as a consuming fire.

The change for us comes in the ransom that has now been fully paid on our behalf through Jesus Christ in his work on the cross. This payment has secured not only our salvation, but our adoption as sons and daughters of the living God. This adoption is most notable in us when we can have such intimate access to God in that we may directly address him as ‘our Father.’ I believe this is the intimacy that Paul is speaking about when he says in Romans 8:15 that we have, “received the Spirit of adoption as sons by whom we cry, ‘Abba Father’.” Paul is describing a new intimacy that the Old Testament people of God could never know without the sacrificial work of Christ and the indwelling presence of the Holy Spirit upon conversion. While it is true that the term “Abba” brings a sense of intimacy with God, it is an intimacy that says more about the new covenant than it does about how much familiarity with which we can address God. Because our direct access to the Father is through Jesus Christ, the New Covenant Church has become the temple of the Holy Spirit and this is an intimacy unknown before the cross.

To suggest that “Abba Father” means “Daddy” is to humanize and possibly even trivialize an intimacy that is so much more gloriously understood in the spectacular blessing of being in the New Covenant. It is so much more glorious when the intimacy is understood through the work of the cross rather than a designation we give to feeble human Dads.