Verse 15

यस्मात्किंचिदवाप्नोषि यस्मिन्वहसि निर्वृतिम् ।तस्मिंश्चेतः शमे मूर्ख नानुबध्नासि किं पदम्

In plain words

That from which you gain something, that in which you would find nirvṛti - in that, O mind, in śama, O fool, why will you not plant your foot?