CATO: Forbear, Sempronius! — see they suffer death,
But in their deaths remember they are men.
Strain not the laws to make their tortures grievous.

Joseph Addison (1672-1719) English essayist, poet, statesman

Cato, Act 3, sc. 5, l. 60ff (1713)
    (Source)

In response to Sempronius' plans to torture the captured rebel soldiers before their execution, as an example to others.