John 10:3-6

To him the doorkeeper opens, and the sheep hear his voice, and he calls his own sheep by name and leads them out. When he puts forth all his own, he goes ahead of them, and the sheep follow him because they know his voice. A stranger they simply will not follow, but will flee from him, because they do not know the voice of strangers.” This figure of speech Jesus spoke to them, but they did not understand what those things were which He had been saying to them.