Bhagavad Gita 18.24
But even though an action involves the most strenuous endeavor, yet if the doer is seeking to gratify their desires and is filled with personal vanity, it may be assumed to originate in passion.
यत्तु कामेप्सुना कर्म साहङ्कारेण वा पुनः।क्रियते बहुलायासं तद्राजसमुदाहृतम्॥yattu kāmepsunā karma sāhaṅkāreṇa vā punaḥ|kriyate bahulāyāsaṃ tadrājasamudāhṛtam||
English translation (above): Shri Purohit Swami (1935), public domain. Sanskrit text via github.com/gita/gita (Unlicense).