Non Possumus

Chambers's Encyclopaedia, Volume 7: Maltebrun to Pearson, p. 516

Non Possumus (Lat., 'we cannot'), a papal formula taken from Acts, iv. 20 (Vulgate), and said to have been used by Pope Clement VII. in reply to Henry VIII.'s demand for the dissolution of his marriage with Catharine of Aragon; used in general expression for the refusal of the Roman curia to yield to the demands of the temporal power.

Source scan(s): p. 0529