Pt. 2 of finale picks up where season 3 finale ended

Part 2 of "There's No Place Like Home" begins exactly where the flash forward moment that ended season 3 left off. As Jack screams "we have to go back!," Kate throws her car into reverse and confronts Jack. She reveals that the obituary is for a man name Jeremy Bentham and that Bentham came to her and she heard what he had to say. She thinks Bentham is crazy but Jack believes they have to go back because Bentham told him that it's the only way to keep Kate and Aaron safe. Kate slaps Jack for saying Aaron's name.

What exactly did Bentham say to Kate when he approached her?