Jesus said in John 10, "
1“Very truly I tell you Pharisees, anyone who does not enter the sheep pen by the gate, but climbs in by some other way, is a thief and a robber.
2The one who enters by the gate is the shepherd of the sheep.
3The gatekeeper opens the gate for him, and the sheep listen to his voice. He calls his own sheep by name and leads them out.
4When he has brought out all his own, he goes on ahead of them, and his sheep follow him because they know his voice.
5But they will never follow a stranger; in fact, they will run away from him because they do not recognize a stranger’s voice.”
This is referring to a kind of basic discernment that all believers should have to know Jesus' voice from any other. But is love the quality of that voice which makes his voice knowable as being from him?
I think it has more to do with a spiritual attachment to him which is a result of predestination.