Yogācārabhūmi Śāstra, Volume 34 (Part 3)

Original text:由十种行观察苦谛。能随悟入苦谛四行。何等为十。一变异行。二灭坏行。三别离行。四法性行。五合会行。六结缚行。七不可爱行。八不安隐行。九无所得行。十不自在行。如是十行依证成道理。能正观察。

Explanation: By observing the truth of suffering through the ten contemplations, one can accordingly awaken to and enter the four contemplations of the truth of suffering. What are these ten contemplations? First, the contemplation of variation; second, the contemplation of destruction; third, the contemplation of separation; fourth, the contemplation of the nature of dharmas; fifth, the contemplation of aggregation; sixth, the contemplation of bondage; seventh, the contemplation of the unlovely; eighth, the contemplation of insecurity; ninth, the contemplation of obtaining nothing; tenth, the contemplation of lack of self-mastery (avaśatā). Through these ten contemplations, relying on the principle of verification and establishment, one can correctly observe.

This passage introduces the ten contemplations. Only by observing the truth of suffering through these ten contemplations can one awaken to and enter the four contemplations of the truth of suffering, and ultimately realize the truth of suffering through these four contemplations.