Srimad-Bhagavatam: Canto 11 - Chapter 1 - Verse 22
Sanskrit:
अथापि नोपसज्जेत स्त्रीषु स्त्रैणेषु चार्थवित् ।विषयेन्द्रियसंयोगान्मन: क्षुभ्यति नान्यथा ॥ २२ ॥
ITRANS:
athāpi nopasajjetastrīṣu straiṇeṣu cārtha-vitviṣayendriya-saṁyogānmanaḥ kṣubhyati nānyathā
Translation:
Yet even one who theoretically understands the actual nature of the body should never associate with women or with men attached to women. After all, the contact of the senses with their objects inevitably agitates the mind.