In spite of the fact that scholars since 1988 have made it clear that "Abba" isn't 'Daddy', preachers and theologians continue to assert confidently that Jesus' address to God reflects a unique relationship, that of child to parent. This unique relationship, they argue, is central to Jesus' teaching and distinct from Judaism. But is "Abba" indeed a unique way to address God and what else might it imply?
Mark's Gospel preserves the one occasion when Jesus addresses God as "Abba." In Mark's account of Gethsemane Jesus prays to be delivered from arrest, torture, and the crucifixion. "Abba, Father, for you all things are possible; remove this cup from me; yet, not what I want, but what you want” (Mark 14.36). Now in Matthew and Luke's versions of Jesus' prayer to God in Gethsemane, Jesus begins the prayer by saying, "My Father…" (Matthew 26:39) and "Father…" (Luke 22.42). In both cases, Jesus addresses God either in the nominative as an address to God (Matthew) or in the vocative as direct address (Luke). Each version uses language of the gospel to which it belongs. Matthew's language connects to the version of the Lord's Prayer, "Our Father, which art in heaven.." (Matt 6.11) and Luke's echoes the version of the Lord's Prayer in Luke 6.3, "Father…" In both cases, the Aramaic word "Abba" and it's Greek equivalent, "Father" found in Mark has entirely disappeared.
So only Mark's gospel preserves the intimacy of Jesus' address to God as "Abba" and this address occurs only in Gethsemane. No other gospel indicates that Jesus prays to God in this way. And Mark's gospel has no version of the Lord's Prayer.
We can agree that only Mark conveys Jesus' use of Aramaic. Now if we assume that Mark's Gospel is the first to be written, and that Matthew and Luke used Mark in the composition of their gospels, then we can see at least two features of Jesus' Aramaic words in Mark: whenever Jesus uses Aramaic, the words are translated into Greek presumably for the sake of Mark's listeners who were not familiar with Aramaic. And in Matthew and Luke's versions of these same stories, Jesus words are recorded only in Greek. If they were ever spoken in Aramaic, hardly a trace remains in Matthew and Luke.
When Jesus heals the daughter of the ruler of the synagogue, he grasps her hand and says, "Talitha koumi" which Mark translates immediately as "Little girl, I say to you, arise!" (Mark 5.41). Matthew 9.25 and Luke 8.54 do not record Jesus' Aramaic words, if there were any. Similarly, Jesus' healing word to the man who was deaf and who had a speech impediment is "Ephphatha!" to which Mark adds, "That is, Be opened!" (Mark 7.34). Any Aramaic words are absent from a parallel passage in Matthew 15.30 and the episode is unrecorded in Luke.
Both Matthew and Mark, however, render slightly different versions of Jesus' cry from the cross in Aramaic, " Eloi, eloi, lama sabachthani!" which they translate as "My God, my God, why have you forsaken me?" (Mark 15.34 and Matthew 27.46). In both gospels, people who hear Jesus' words in Aramaic mistakenly think he is calling Elijah. They didn't have the benefit of Mark's or Matthew's renditions because they were living, not hearing, the gospel. And they didn't hear Psalm 22.
So whether in healings, or in a prayer for deliverance, or a cry of despair, Mark's gospel preserves and translates Jesus' Aramaic exclamations. Except for Matthew's account of Jesus' last words, when Matthew, Luke and John report these healings or events, Mark's Aramaic words are eliminated or simply not mentioned.
The fact that Mark translates Jesus' Aramaic speech is worth noting. Think about Jesus' prayer in Gethsemane for a minute. Is it likely that Jesus uttered a bilingual prayer in Gethsemane using both Aramaic and Greek in the opening petition? Probably not. But Mark renders the scene by keeping the strangeness, even the magical character of the Aramaic at the same time as translating the foreign words into Greek. So he moves hearers from the unknown language of Aramaic to the more universally known one, Greek. And Mark translates "Abba" not as "Daddy" but as "Father".
Now when Jesus addresses God as "Father," Jesus joins his petition for deliverance to those of other Jews in his time e.g. Sirach 23.1,4; and Wisdom 14.3. In 4Q372 1.16, the "Joseph prayer," Joseph calls God "my Father" and pleads that God would save him from the hands of the Gentiles. So to argue that no contemporary Jewish prayer contains this form of address for God is to ignore the evidence. Jesus is a devout Jew whose prayer language fits with his time and place.
Further, to argue that Jesus' use of "Abba" is unique is simply not true. On two occasions in his letters, Romans 8.15 and Galatians 4.6, Paul describes "Abba, Father!" as the cry of newly adopted believers calling on a relationship to God they can now claim as their own. Paul's letters predate the gospels. The cry "Abba, Father!" recorded by Paul expresses the ecstatic speech of those newly adopted into the faith from a Gentile background in Asia Minor or elsewhere. It seems unconnected to Jesus' petition for deliverance at Gethsemane. On the lips of Paul's addressees, it is the cry of outsiders becoming insiders, perhaps as they take part in a ritual signaling transference, not an insider praying for escape from something awful about to happen.
So it might be better to say that Jesus' address of God as "Abba" is distinctive rather than unique. It is part and parcel of the religious prayer language of Jesus' day. What makes it distinctive is that it reflects language Jesus used that Mark regards as secret, and perhaps even magical. As such, it needs to be translated into Greek every time Jesus uses it. How extraordinary it is that so many interpreters cling to "Abba" as indicating Jesus' unique relationship to God in mysterious language from which gospel writers seek to escape!
© Deirdre Good is professor of New Testament at The General Theological Seminary, specializing in the Synoptic Gospels, Christian Origins, Noncanonical writings and biblical languages. An American citizen, she grew up in Kenya and keeps the blog http://www.notbeingasausage.blogspot.com/ .
More from this author on Ekklesia: http://www.ekklesia.co.uk/taxonomy/term/2258 
This article is reproduced from the Daily Episcopalian (http://www.episcopalcafe.com/ ) with grateful acknowledgements to them and to Professor Good.