Shin Buddhist Service Book P.77
Sanbutsuge comes from The Larger Sutra of Immeasurable Life. It is the praises voiced by Bodhisattva Dharmakara to the Buddha Lokesvraraja.
In these praisesDharmakara expresses his own desire to attain Buddhahood and his heartfelt determination to accomplish his goal for the sake of saving all sentient beings. (SBSB)