Paul describe a relationship with God as a Father. Such a close relationship that we actually can call Him Father.

 Those who are led by God’s Spirit are God’s children. For the Spirit that God has given you does not make you slaves and cause you to be afraid; instead, the Spirit makes you God’s children, and by the Spirit’s power we cry out to God, “Father! my Father!” God’s Spirit joins himself to our spirits to declare that we are God’s children. – Romans 8:14-16 GNT

This is a really big deal. I think we may have lost how profound this is. We cry out – not a hesitant whisper with uncertainty but with a confidence that comes from our heart and our voice. It is a prayer and a praise. Whether I express it out audibly or just in my thoughts, internalized, I can call Him my Father. The Holy Spirit has been deposited within me as the first part of my inheritance and He moving in me gives me confidence to cry out – my Father.

Prayer is me praying to God the Father through the Son and by the Spirit.

Someone once asked G. Campbell Morgan, after preaching a sermon in London, “Pastor, can I pray for little things, or only big things, when I pray to God?” He said to her, “Ma’am, everything in your life is little compared to God.”

I cry out to my Father for everything because the Holy Spirit has transformed me from a slave to His child. It is the Spirit of God that has created within me an awareness of this sense of intimacy and acceptance with the Father.

The transformation takes place when the Spirit enables me to believe in Christ and to understand my new position as an adopted child of God and all the privileges that now apply to me and result in me being changed. My new relationship means I cry out – my Father – an emotional word used in the prayers uttered in the Psalms 40 times.

My Father was the address Jesus used as He prayed in the Garden just prior to His arrest and He taught us how to pray starting with this expression. It means that I can draw near to God in my distress and my time of need with the same sense of intimacy and assurance of being heard that Jesus had.

“In the Aramaic of Jesus’ time abba, in origin
an exclamation of small children, had replaced
in ordinary use abi (‘my father’), both vocative
and non-vocative, and also the emphatic state
aba. It was not, however, used as a form of
address to God (its homely origin no doubt
made it seem unsuitable). So its use by Jesus is
highly significant… It is significant that Jesus
calls God ‘Father’ at this moment – as he sees
the cup held out to him. He knows God as
Father even in Gethsemane: to have failed to
do so would have been to lose the battle.”
Cranfield