Subsequently, he was at St Mary's, Edge Hill, an important church in Liverpool, for 19 years.

As metropolitan of Australia he was also concerned with the establishment of dioceses at Perth (1856), Brisbane (1859), Grafton and Armidale (1866), Ballarat (1875), and North Queensland (1878).

In 1878 steps were taken to provide more adequate religious instruction to children attending state primary schools, and a church buildings loan fund for the diocese of Sydney was established early in 1880.

There was an improvement for some months, but in March 1882 he had a second attack and died at San Remo, Italy, on 6 April 1882.

He published Thirty-six Psalms with Commentary and Prayer (1851), and A Charge Delivered to the Clergy of the Diocese of Sydney (1859).

Due to his height and his abstinence from alcohol, the term 'Bishop Barker' was jocularly applied to the tallest beer glass available in late-19th-century Sydney hotels.