維摩經玄疏 6.67

6.67

Third, explaining the use of the four siddhāntas to generate the teachings of the four doors: the four doors of the non-Buddhists do not perceive faculties and conditions, but adhere to mental grasping and fixated assertions of characteristics, like an old physician who always uses milk medicine to treat all illnesses; these do not generate the four doors by relying on the four siddhāntas. Now, the four doors of the Buddha-Dharma are all generated due to the four siddhāntas: first, explaining the siddhāntas generating the four doors of the Tripiṭaka teaching; second, explaining the siddhāntas generating the four doors of the shared teaching; third, explaining the siddhāntas generating the four doors of the distinctive teaching; fourth, explaining the siddhāntas generating the four doors of the perfect teaching.