無量壽經優婆提舍願生偈註 2.178

2.178

示應化身者，如《法華經》普門示現之類也。遊戲有二義：一者自在義。菩薩度眾生，譬如獅子搏鹿所為不難，如似遊戲。二者度無所度義。菩薩觀眾生畢竟無所有，雖度無量眾生，而實無一眾生得滅度者，示度眾生如似遊戲。言本願力者，示大菩薩於法身中常在三昧，而現種種身、種種神通、種種說法，皆以本願力起。譬如阿修羅琴，雖無鼓者而音曲自然。是名教化地第五功德相。

Manifesting responsive transformation-bodies refers to kinds of manifestations like the Universal Gate in the Lotus Sūtra. 'Sporting' has two meanings: First, the meaning of mastery. A bodhisattva saving sentient beings is like a lion seizing a deer: what is done is not difficult, as if it were sport. Second, the meaning of saving without anything saved. A bodhisattva contemplates that sentient beings are ultimately non-existent; though saving immeasurable sentient beings, in truth not a single sentient being attains nirvāṇa; manifesting the saving of sentient beings is like sport. As for the 'power of the fundamental vow,' it indicates that the great bodhisattva, while constantly in samādhi within the Dharma-body, manifests various bodies, various spiritual powers, and various teachings of the Dharma, all arising through the power of the fundamental vow. It is like the Asura's harp: though there is no player, melodies naturally sound. This is called the characteristic of the fifth merit of the ground of teaching and transforming.