The train door opened, revealing a man brandishing a very long, very sharp kitchen knife. For a moment I remained paralysed. Should I run away? But the... train steward? ...greeted me pleasantly, so I smiled back and went on my way as though my heart wasn't performing uncomfortable antics in my chest. Back in my seat, a member of my group said they'd seen the steward making sandwiches earlier. Knife explained; false alarm. But having just - belatedly - heard about the martyrdom of Fr Jacques in France, cooking wasn't the first thing that came to mind on a train, and this totally insignificant incident was actually, for me, a moment of profound challenge.