[citation needed] After his father's death in 1747, Jennens had Gopsall Hall completely rebuilt in the Palladian style, including within the estate an Ionic temple built in memory of his friend, the poet and classical scholar, Edward Holdsworth.
His memorial lies in Nether Whitacre Parish Church and was sculpted by Richard Hayward who also provided sculptures both in his London home at Great Ormond Street and at his country seat of Gopsall Park.
[2][8] Jennens' extensive collection of books by William Shakespeare, on literature, philology and theology was largely dispersed in a sale in 1918.
Saul and Belshazzar are said to "show an impressive gift for dramatic structure and characterization and the ability to wield political analogies adroitly.
"[2] Well versed in music as well as literature, he annotated his copies of Handel's operas, adding corrections, bass figures, rejected pieces and dates.
[11] Musicologist Watkins Shaw describes it as "a meditation of our Lord as Messiah in Christian thought and belief", and which "amounts to little short of a work of genius".
[3][13] Jennens was less than wholly approving of the musical setting, writing to Edward Holdsworth: "I shall show you a collection I gave Handel, called Messiah, which I value highly.
"[14]In the early 1770s, Jennens commenced the preparation of scrupulous critical editions of Shakespeare plays, and the first time that these had been published individually and with editorial footnotes.