The Gohonzon
The Altar

The object of devotion in the form of a scroll inscribed with Chinese and Sanskrit characters is the focal point for chanting Nam-myoho-renge-kyo and reciting the sutra during gongyo.  Nichiren taught that one should have faith in this Gohonzon as the object of devotion for attaining Buddhahood.  

Nichiren defined the ultimate Law permeating life and the universe to be Nam-myoho-renge-kyo and embodied it in the form of a mandala, on this Gohonzon.  In Japanese, an object of devotion is called honzon, which means object of fundamental respect.  Go is an honorific prefix.