Final answer:
The Book of Revelation in the Christian Bible contains the first mention of Satan's ultimate defeat.
Step-by-step explanation:
The first mention of Satan's ultimate defeat can be found in the Book of Revelation in the Christian Bible. In this book, there is a passage that describes the final battle between Christ and Satan, where Satan is ultimately defeated.
An example of this can be seen in Revelation 20:10, which states, 'And the devil who had deceived them was thrown into the lake of fire and sulfur where the beast and the false prophet were, and they will be tormented day and night forever and ever.'
These verses indicate that Satan will be defeated and punished for eternity, symbolizing the ultimate triumph of good over evil.