abba is a vocative address to Father in direct prayer and Spirit-enabled crying.

Across the supplied verses, Αββα is used as a singular masculine vocative address to Father: in direct prayer and in cries associated with receiving the Spirit and adoption as sons.

1. Vocative address to Father · dominant

   All three occurrences use Αββα as a singular masculine vocative. In Mark 14:36 the APB renders the prayer, "Abba, Father, all things are possible for you"; in Romans 8:15 and Galatians 4:6 it renders cries of "Abba, Father" in contexts of adoption as sons and the Spirit in believers' hearts.

   Galatians 4:6Mark 14:36Romans 8:15

In the Anselm Project Bible: The APB presents the form as "Abba" followed by "Father" in each verse, both in direct prayer and in cries. The supplied text does not establish how the two English words divide between the original terms.