BG 18.59
यदहङ्कारमाश्रित्य न योत्स्य इति मन्यसे।मिथ्यैष व्यवसायस्ते प्रकृतिस्त्वां नियोक्ष्यति
yad ahankāram āśhritya na yotsya iti manyase mithyaiṣha vyavasāyas te prakṛitis tvāṁ niyokṣhyati
If you in your vanity think of avoiding this fight, your will shall not be fulfilled, for Nature herself will compel you.
Translated by Shri Purohit Swami
If, filled with egoism, thou thinkest, "I will not fight," then thy resolve is vain; nature will compel thee.
Translated by Swami Sivananda
Word meanings (from the gita/gita dataset)
yat—if; ahankāram—motivated by pride; āśhritya—taking shelter; na yotsye—I shall not fight; iti—thus; manyase—you think; mithyā eṣhaḥ—this is all false; vyavasāyaḥ—determination; te—your; prakṛitiḥ—material nature; tvām—you; niyokṣhyati—will engage