Uttarajjhayana 16.5

16.5

no itthīṇaṃ iṃdiyāiṃ maṇoharāiṃ maṇoramāiṃ āloittā, nijjhāittā havai, se niggaṃthe|
taṃ kahamiti ce?
āyariyāha–niggaṃthassa khalu itthīṇaṃ iṃdiyāiṃ maṇoharāiṃ, maṇoramāiṃ āloemāṇassa, nijjhāyamāṇassa baṃbhayārissa baṃbhacere saṃkā vā, kaṃkhā vā, vitigicchā vā samuppajjijjā, bheyaṃ vā labhejjā, ummāyaṃ vā pāuṇijjā, dīhakāliyaṃ vā rogāyaṃkaṃ havejjā, kevalipannattāo vā dhammāo bhaṃsejjā| tamhā khalu niggaṃthe no itthīṇaṃ iṃdiyāiṃ maṇoharāiṃ, maṇoramāiṃ āloejjā, nijjhāejjā|

A Nirgrantha does not look at or gaze upon the charming, delightful limbs of women.
Why is that?
The ācārya says: If a Nirgrantha practicing celibacy looks at or gazes upon the charming, delightful limbs of women, there may arise in his celibacy doubt, longing, or uncertainty, or he may suffer a breach, or incur madness, or contract a long-lasting and painful illness, or fall away from the Dharma taught by the omniscient ones.
Therefore, indeed, a Nirgrantha should not look at or gaze upon the charming, delightful limbs of women.