Replying to The Box (Movie)?

I just watched the movie "The Box"

Overall I thought it was an incredible movie, if not only because it held my attention so thoroughly that I could not get off the couch once. But, it left me very confused on a few points, mainly:

What happened in the part in the library where he goes to the woman and she leads him to the three columns of water? I understand that two would be damnation and one salvation, but what happened there?

Thanks.