In John 10, Jesus talks about how the sheep will recognize the voice of their shepherd. NT Wright shares an experience that further illustrates the power of this passage:
“We stood on the cliffs and watched as the mother birds swooped in from the sea with mouthfuls of fish. There, below us, were thousands, probably tens of thousands, of young birds, all waiting eagerly, all screaming their peculiar cry. They were all jostling and pushing, falling over and scrambling about. Somehow, unerringly, the mothers picked out the single voice of their own chick from the teeming, noisy crowd. It seemed like a miracle. … But those of us who don’t have much to do with the bird and animal kingdoms on a daily basis are often startled at just how much animals can distinguish between different people as well as between other members of their own species. To this day, in the Middle East, a shepherd will go into a crowded sheepfold and call out his own sheep one by one, naming them. They will recognize his voice and come to him” (Wright, John for Everyone, Part 2,147–48).