大乘起信論義疏 1.14

1.14

自下二句明立正也。言「起大乘正信」者，正者非曲為義，餘義釋同前也。何故起此信者？下題其意，「佛種不斷故」。立信之人修行能得常住佛果，故經言「生信心者生諸佛家」，已種佛種。《勝鬘經》四種真子中，初真子者即是其事，紹佛位故名真子。此之初段竟。

Next, the subsequent two phrases clarify establishing the orthodox. The words 'generate correct faith in the Mahāyāna': 'correct' has the meaning of not being crooked; the rest of the meaning is explained as before. Why generate this faith? Below, the intention is stated: 'so that the Buddha-seed may not be cut off.' One who establishes faith and cultivates practice can attain the eternally abiding fruit of Buddhahood; hence the sūtra says, 'One who generates a mind of faith is born into the family of all Buddhas,' already having planted the Buddha-seed. Among the four kinds of true sons in the Śrīmālā Sūtra, the first true son is precisely this matter; because he succeeds to the Buddha's position, he is called a true son. This concludes the first section.