Abba
Abba [Grk. abba, from Heb. ha’ab; Aram. ’abba’ “the father”]. A child’s address of his/her father; a reference to God in prayer.
Jesus’ use of Abba toward God was a unique and extremely intimate way of addressing God (Mark 14:36). By this address, Jesus indicated God is a person, not an abstract concept. In His agony and in view of the forthcoming passion and death, Jesus revealed His strong bond with the Father. A similar sonship is promised to Christians. In Galatians 4:4-6 and Romans 8:14-17 Paul assures that the Spirit of Christ builds the same intimate connection of a human to God and is a mark of adoption of the believer.