Puruṣottama Yoga · Verse 11
यतन्तो योगिनश्चैनं पश्यन्त्यात्मन्यवस्थितम् | यतन्तोऽप्यकृतात्मानो नैनं पश्यन्त्यचेतसः
yatanto yoginaś cainaṃ paśyanty ātmani avasthitam | yatanto 'py akṛtātmāno nainaṃ paśyanty acetasaḥ
The striving yogins see Him established in the Self; but those of undisciplined mind, though they strive, do not see.
Contrast between two types of yatat (striving, making effort). The yoginaḥ who have disciplined their mind paśyanti (see) the jiva established in the ātman — in the supreme Self.
But the akṛtātman — those whose Self has not been realized, who have not worked on themselves — even yatantaḥ api (though they strive), do not see. They are acetasaḥ — of unfixed mind, without cetanā (conscious attention). Effort without inner preparation is useless; vision requires mental discipline.