The scene in Ford's ghost cabin in episode 6. Bernard walks into the cabin and is quickly grabbed by the host of Ford's father. Bernard's voice commands do not work on the host and the moment things turn south, Ford appears out of thin air. I've read a few comments that people believe Ford froze all the hosts in this cabin, traveled from wherever he may have been, and unfroze them as soon as he was present in the cabin. We are seeing this scene from Bernard's perspective. If Bernard was frozen in time, as Ford has the ability to do to hosts, then Ford would have looked to appear out of thin air when Bernard was then unfrozen. Interesting.