Saying one thing while meaning another, often the opposite. The true sense is left to whoever reads or hears.
In Crime and Punishment
So it is a symbol that I am taking the cross upon myself, he-he! And it's true, until now I have suffered very little!
The “he-he” and “until now I have suffered very little” give the sentence a mocking tone. Raskolnikov speaks of the symbol as one who makes fun of it, and sarcasm protects him from what Sonia's gesture makes him feel.