Bhagavad Gita 2.60

O Arjuna! The mind of one who is attempting to conquer it is forcibly carried away, in spite of their efforts, by their tumultuous senses.

यततो ह्यपि कौन्तेय पुरुषस्य विपश्चितः।
इन्द्रियाणि प्रमाथीनि हरन्ति प्रसभं मनः॥

yatato hyapi kaunteya puruṣasya vipaścitaḥ|
indriyāṇi pramāthīni haranti prasabhaṃ manaḥ||

English translation (above): Shri Purohit Swami (1935), public domain. Sanskrit text via github.com/gita/gita (Unlicense).