Possible Clues:

• Rural clergyman, a local leader
• Out of town, having got through the viva voce, by the sound of it
• Symphony, for the audience, didn't fail the test
• Of sheperds, or concerned with spiritual guidance
• Sort of poetry and history exam
• Minister, a Labour leader of the country
• (Poem) of country life
• Of shepherds; pupil-welfare (responsibility)
• Letter to church members from bishop's staff
• Musical composition is overstated