This could be Arthur Koestler apostrophizing the condemned Rubashov in his novel Darkness at Noon (1940):

There is nothing more difficult than to be a stepson of the time; there is no heavier fate than to live in an age that is not your own. Stepsons of the time are easily recognized: in personnel departments, Party district committees, army political sections, editorial offices, and on the street. Time loves only those it has given birth to itself: its own children, it own heroes, it own labourers. Never can it come to love the children of a past age, any more than a woman can love the heroes of a past age, or a stepmother love the children of another woman.

In fact, it is from Vasily Grossman’s masterpiece of World War II, Life and Fate (1959). If Fascism doesn’t kill Krymov, the graying commissar of the novel, then his own obsolescence under Stal ...