Most assuredly, I tell you, the hour comes, and now is, when the dead will hear the Son of God's voice; and those who hear will live.
And He begins to talk to them now, emphasizing what He's saying with these words verily, verily. And the repetition of the word is for emphasis, it's, "Alright, now hear this." I mean, it's really calling their attention to what I'm about to say.