It is curious, but till that moment I had never realized what it means to destroy a healthy, conscious man. When I saw the prisoner step aside to avoid the puddle, I saw the mystery, the unspeakable wrongness, of cutting a life short when it is in full tide....and in two minutes, with a sudden snap, one of us would be gone — one mind less, one world less.Orwell - A Hanging
Fyodor Dostoyevsky was sentenced to death for being a member of a revolutionary group. The first batch of convicts was facing the firing squad and Dostoyevsky was in the second batch when a pardon arrived. The execution was meant to be mock all along. The horror of the experience never left Dostoyevsky who wrote about it in his novel The Idiot.
....there may be men who have been sentenced, who have suffered this mental anguish for a while and then have been reprieved; perhaps such men may have been able to relate their feelings afterwards.
Arthur Koestler was awaiting execution in a condemned cell in Franco's Spain, and was released in a prisoners exchange. He wrote about his experiences in Dialogue with Death/Spanish Testament. Later, he was one of the forces behind the successful campaign against Capital Punishment in Britain. The frontispiece of the book had this poem by Swinburne with which comforted himself during his incarceration -
Pray thou thy days be long before thy death,
And full of ease and kingdom; seeing in death
There is no comfort and none aftergrowth,
Nor shall one thence look up and see day's dawn
Nor light upon the land whither I go.
Live thou and take thy fill of days and die
When thy day comes; and make not much of death
Lest ere thy day thou reap an evil thing.
Thomas Mann's reaction to Edith Cavell's execution was unsympathetic. He mocked her reported fainting while facing the firing squad in his Reflections of a Non-Political Man.