Julian's account:
Robert Hawker, M.D. was born at Exeter in 1753, and educated for the medical profession. In 1778 he was ordained, and in 1784 became Incumbent of Charles the Martyr Church in Plymouth, where he remained until his death on April 6th. 1827. Dr. Hawker was well known as a controversial and theological writer. His name is also associated with hymns, especially "Lord, dismiss us with Thy blessing" and a few others. He published "Psalms and Hymns Sung by the Children of the Sunday School in the Parish Church of Charles, Plymouth, at the Sabbath Evening Lecture, N.D. (c. 1787)" This collection is noticeable as having been one of the first hymn books published in connection with the Sunday School movement. It had some influence on later collections. It passed through 13 editions and was widely used when Sunday Schools became more numerous.
R. Hawker has two hymns in 'Spiritual Songs':
No. 104. "Abba, Father, thus we call Thee". "Abba, Father! Lord we call Thee" was Hawker's original rendering, followed by 1856, "Abba, Father, God we call Thee" (1894)
No. 379. "We bless Thee, O Thou great Amen!" All editions from 1856 to 1978 have these two hymns.