In the letter dated 24 April 1775, Thomas writes that the ‘patriarch of Ferney’ [Voltaire] speaks at ease about envy, noting that ‘it is Apollo who speaks on the body of the serpent Pithon struck down at his feet. But the teeth of the monster are terrible, and not everyone has the arrows of the god. I wish you one of the arrows from his quiver. It is up to you to irritate the monster and to defeat him.’
In the letter dated 7 July 1775, Thomas writes that he was astonished to see his private letters printed in the Mercure as they are not suitable for the public eye. He quips that ‘Mr de Voltaire alone can have this right; all that escapes from his pen, can interest, and his praises become titles.’
In the letter dated 14 July 1778, Thomas deplores the circumstances of Voltaire’s funeral, and the prohibition of publicity and theatrical representation that followed his death.
In the letter dated 6 February 1779, he discusses the eulogy of Voltaire proposed by the academy, arguing that it must ‘awaken all the talents’ because ‘in celebrating him, one must speak his language, and verses worthy of him are the most beautiful homage.’

Voltaire writes that he has been exploring multiple genres of literature whilst in his ‘retreat’ though he has kept this from being public knowledge because ‘I realise every day that one must live and think for oneself, and that the chimera of reputation does not console the sorrows it drags after oneself.’ He adds that he will be very grateful if the marquis could extract from the letters he told Voltaire about anything pertaining to the history of the last century, noting that he does not know if Louis XIV deserved the name of ‘great’ but that his century did and it is of its art and letters that Voltaire wishes to write. He then turns to Newton’s philosophy saying that it has gained some ground in Paris among true philosophers but that the city is dominated by ‘Molinist and Jansenist nonsense’. However, he adds that all of this is overshadowed by the crisis in which Europe finds itself, drawing classical comparisons. He ends by saying that he has always desired a climate such as that that the marquis lives in and wishes to be with him under the beautiful sun with English philosophers and Italian voices.