Though he had lit­tle school­ing, Ros­coe worked for an at­tor­ney and sub­se­quent­ly prac­ticed law in Liv­er­pool un­til 1796. He then turned to his first love, lit­er­a­ture. He was a strong an­ti-slav­ery ad­vocate, and Mem­ber of Par­lia­ment from Liv­er­pool in 1807. He con­trib­ut­ed eight hymns and the con­clud­ing an­them to the Uni­tar­i­an Se­lect­ion of Psalms and Hymns for Pub­lic and Pri­vate Wor­ship, 1818. His works in­clude:

• Mount Plea­sant, 1773
• The Wrongs of Af­ri­ca, 1787, 1788
• Ode to the Peo­ple of France,1789
• Life of Lo­ren­zo dé Me­di­ci 1796
• Life and Pon­tif­i­cate of Leo the Tenth, 1805
• The But­ter­fly’s Ball and the Grass­hop­per’s Feast 1807
• Illustrations of the Life of Lo­ren­zo dé Me­di­ci, 1796

• Julian, p. 977

1. Let Our Loud Song of Praise Arise
2. Go, Suf­fer­ing Habitant of Earth
3. Great God! Be­neath Whose Pierc­ing Eye
4. Thus Said Je­sus, Go and Do
5. What Is the First and Great Com­mand?