A voice you know

In the Middle East, shepherds sometimes brought their flocks together in one fold for the night. In the morning each shepherd called his own sheep. They came to his voice and wouldn't go off with a stranger. Travellers were still describing this in the twentieth century.

Jesus says: my sheep hear my voice. They don't recognise him by knowing a lot, but by familiarity, the way you know a voice you've heard many times. And it starts with him: I know them. Whoever follows him has first been known.