Priestley defended his friend in the pamphlet Letter to a Layman, on the Subject of the Rev. Mr. Lindsey's Proposal for a Reformed English Church (1774), claiming that only the form of worship had been altered, not its substance, and attacking those who followed religion as a fashion.
Priestley membela rekannya tersebut dalam pamflet Letter to a Layman, on the Subject of the Rev. Mr. Lindsey's Proposal for a Reformed English Church (1774), mengkaim bahwa hanya bentuk peribadatannya saja yang diubah, dan bukan substansinya, serta menyerang mereka yang hanya mengikuti agama sebagai mode.