*Yogācārabhūmi-śāstra*, Volume 53

Original text: 若依未至定证得初果，尔时一切能往恶趣恶戒种子皆悉永害，此即名为圣所爱戒。

This clearly states that when one attains the stream-enterer fruit (Srotaāpanna), one must possess preparatory concentration (anāgamya-samādhi); only after realizing the fruit can the karmic seeds of the three evil destinies be eliminated and no longer arise. When the karma leading to the three evil destinies is no longer created, this is called the preceptual conduct cherished and delighted in by the noble ones.

If preparatory concentration is not complete, or if there is no preparatory concentration at all, one cannot actually engage in contemplative practice (vipaśyanā-caryā) upon the five aggregates (pañcaskandha), cannot truly reject the self of the five aggregates, and the view of the self of the five aggregates cannot be eliminated; thus one cannot realize the fruit. The mind consciousness may hold the view that the five aggregates are without self, but holding that view is not realization—it belongs to intellectual understanding. Only realization counts as realization; only with unshakable certainty can the bond of views be severed.

Meditative concentration is tightly connected with the manas. With meditative concentration, the manas can remain unobscured by afflictions and delusive thoughts, undisturbed by the ceaseless discernment of the six consciousnesses, allowing one to practice diligently and thereby realize the fruit and clearly understand the truth.