大方廣圓覺修多羅了義經略疏 1.150

1.150

八、修證階差者，謂若但約教文唯生義解，忘詮修證復有其門，故以心傳心歷代不絕。自佛屬迦葉展轉于今，燈燈相承明明無盡。然所傳法不出定慧、悟修、頓漸。無定無慧是狂是愚，偏修一門無明邪見，此二雙運成兩足尊，故天台修行宗於止觀。

Eighth, regarding the stages and distinctions of practice and realization: if one relies solely on the doctrinal texts, only conceptual understanding is generated; there is another gateway for practice and realization that forgets verbal formulation. Therefore, transmission from mind to mind has continued unbroken across generations. Transmitted from the Buddha to Kāśyapa down to the present day, one lamp passing to another, its illumination is endless. Yet the Dharma transmitted does not go beyond samādhi and prajñā, awakening and cultivation, sudden and gradual. Without samādhi and without prajñā, one is either reckless or foolish; cultivating only one gate leads to ignorance and false views. When these two are exercised together, one becomes the Double-Sufficiency Honored One. Therefore, Tiantai's cultivation takes śamatha and vipaśyanā as its core.