法華義疏 4.124

4.124

彼明一念善具二因，今明有所得善，前後相生義自是習因，感報之義是報因，此之習報並是不成佛。故《法華論》釋「童子聚沙為佛塔皆已成佛」者，要是發菩提心方得成佛，非謂凡夫善根及決定聲聞善根得成佛也。《中論》云「雖復懃精進修行菩提道，若前非佛性終不得成佛」也。

They explain that a single thought of goodness possesses both causes. We now explain that for goodness with apprehension, the sense of earlier and later producing one another is itself the habituation cause, while the sense of inducing retribution is the retributive cause; both this habituation and retribution do not attain buddhahood. Therefore, when the *Fahua lun* explains 'children who gather sand into a stūpa of the Buddha have all already attained buddhahood,' it means that one must give rise to the bodhicitta before one can attain buddhahood; it does not mean that the good roots of an ordinary being or the good roots of a determined śrāvaka can attain buddhahood. The *Mūlamadhyamakakārikā* states: 'Even if one diligently and vigorously cultivates the path of bodhi, if previously there were no buddha-nature, one would ultimately never attain buddhahood.'