The most formidable enemy lies within oneself.

The only thing in the balance is the fight within oneself. The battle is ongoing, but there will be a final strike given. A victor crowned. The champion left standing is the one you chose to train.

http://scriptures.lds.org/en/abr/3/25#25

25 And we will prove them herewith, to see if they will do all things whatsoever the Lord their God shall command them;