Context

Jesus speaks these words right after Peter cuts off the ear of the servant of one of the high priests. 

Judas Iscariot and a mob are there to arrest Jesus, and Peter's like, "Not on my watch." But Jesus tells him that he's got it under control, and he lets himself be arrested.

Where you've heard it

Often quoted as, "Those who live by the sword die by the sword," this line is usually quoted ironically to describe any kind of poetic justice or karma—like when an off-duty tow truck driver gets towed himself.

Sorry, dude. We know it's just your job.

Pretentious Factor

If you were to drop this quote at a dinner party, would you get an in-unison "awww" or would everyone roll their eyes and never invite you back? Here it is, on a scale of 1-10.

This quote can carry significant emotional weight. That means it might sound pretentious in a serious situation, but can be perfectly unpretentious when applied to a food fight, prank war, or free-for-all battle royale amateur heavyweight championship backyard cage match.