Yōga Sūtra 4.03

निमित्तमप्रयोजकं प्रकृतीनां वरणभेदस्तु ततः क्षेत्रिकवत्।

nimittamaprayōjakaṁ prakr̥tīnāṁ varaṇabhēdastu tataḥ kṣētrikavat।

[निमित्तम् अप्रयोजकं प्रकृतीनां वरण भेदस्तु ततः क्षेत्रिक वत्।
nimittam = is only incidental; aprayōjakaṁ = not much useful; prakr̥tīnāṁ = nature; varaṇa = covering; bhēdastu = to unveil; tataḥ = just; kṣētrika = cultured agriculture field; vat = like;]

To unveil the covering, nature is only incidental and not much useful, just like a cultured agriculture field.