大方便佛報恩經 2.54

2.54

爾時喜王菩薩復白佛言：「世尊！菩薩知恩，自發菩提心；菩薩報恩，教一切眾生令發菩提心者；如來世尊於生死時初發菩提心，因何事發？」

At that time, the bodhisattva Prītirāja spoke to the Buddha again, saying: "Bhagavat! If a bodhisattva knowing kindness generates the bodhimind oneself, and a bodhisattva repaying kindness teaches all sentient beings to generate the bodhimind, then when the Tathāgata, the Bhagavat, first generated the bodhimind while in saṃsāra, by what cause did you generate it?"