An interesting question: If you had to flee for your life, only taking what you could carry, knowing you might never come home again, what's the one precious thing you would be sure you had as you went out the door? I'm not sure I have a definite answer myself.
But many Iraqi Christians have had to answer that question for real in a hurry, and not hypothetically at leisure. Photographer Matt Cardy at a refugee camp for Iraqi Christians who have had to flee home has a short series of portraits of refugees with that one thing they had to grab as they fled. The portrait of Rafo Polis is the best one, but they are all poignant.