In a world of frenetic activity, to hear the call requires positioning oneself in God’s presence long enough to hear God say, “Whom shall I send?” Disciples are the only category of Christians I know who are in the place of responding because they’re close enough and disciplined enough to spend time with God and hear his voice. God is always asking, “Whom shall I send?” But not everyone is listening. The call is there for everyone. The call has gone out to everyone. But not everyone is available to hear and receive the call until the discipline is in place.