[2] His 1924 Bampton Lectures were published in 1927 under the title The Ideas of the Fall and of Original Sin, which continues to be an influential source for students of original sin to this day and was included in Ronald W. Hepburn's 1973 entry on the "Cosmic Fall" in the Dictionary of the History of Ideas.

Williams argued for a "transcendental" or "pre-cosmic fall" that occurred in the "life-force" and "during an 'absolute' time" prior to the "differentiation of life into its present multiplicity of forms and the emergence of separate species.

A collected edition of his works was published by Eric Waldram Kemp in 1954, entitled simply N. P. Williams.

On the flap jacket of this edition, N. P. Williams was given this description: The young cleric cocking a snook at dignitaries -- the powerful controversialist -- the brilliant, sometimes perhaps too brilliant theologian with his sesquipedalian eloquence -- beneath these and more essential than these was a good friend, a devoted husband and father, a true priest with pastoral zeal and wide charity.

A shy, diffident person, not easy to live with but easy to love, and certainly worthy of being remembered and honoured for himself.Williams married Muriel, daughter of Arthur Philip Cazenove, of a landed gentry family;[5] their son was Charles Williams, Baron Williams of Elvel.