Bhagavad Gita · 2.68

तस्माद्यस्य महाबाहो निगृहीतानि सर्वशः।इन्द्रियाणीन्द्रियार्थेभ्यस्तस्य प्रज्ञा प्रतिष्ठिता॥

tasmād yasya mahā-bāho nigṛihītāni sarvaśhaḥ indriyāṇīndriyārthebhyas tasya prajñā pratiṣhṭhitā

Therefore, O mighty-armed one, one whose senses are completely restrained from sense objects has steady wisdom.

— Bhagavad Gita 2.68

Source: Sacred-Texts.com (Sanskrit) + Bhagavad-Gita.io (translations)