菩薩戒本疏 2.26

2.26

若佛子！心背大乘常住經律，言非佛說，而受持二乘外道惡見、一切禁戒、邪見經律者，犯輕垢罪。

"If a disciple of the Buddha turns their mind away from the eternal sūtras and vinaya of the Mahāyāna, saying they are not the Buddha's preaching, and instead receives and upholds the pernicious views of the two vehicles and heterodox paths, all their prohibitions, precepts, and wrong-view sūtras and vinaya, they commit a duṣkṛta offense."