[236] Bhikkhus, this holy life (brahmacariya) is lived without a resident pupil (antevāsika) and without a teacher (ācariya). Bhikkhus, a bhikkhu who has a resident pupil and who has a teacher dwells in suffering (dukkha), not at ease; a bhikkhu without a resident pupil and without a teacher dwells happily, at ease. And how, bhikkhus, does a bhikkhu who has a resident pupil and who has a teacher dwell in suffering, not at ease? Here, bhikkhus, when a bhikkhu has seen a form with the eye, there arise in him evil, unwholesome states, memories and intentions connected with the fetters. These dwell within him; since evil, unwholesome states dwell within him, therefore he is called "one with a resident pupil." These assail him; since evil, unwholesome states assail him, therefore he is called "one with a teacher." … Furthermore, bhikkhus, when a bhikkhu has tasted a flavor with the tongue, there arise in him evil, unwholesome states, memories and intentions connected with the fetters. These dwell within him; since evil, unwholesome states dwell within him, therefore he is called "one with a resident pupil." These assail him; since evil, unwholesome states assail him, therefore he is called "one with a teacher." … Furthermore, bhikkhus, when a bhikkhu has cognized a dhamma with the mind (mano), there arise in him evil, unwholesome states, memories and intentions connected with the fetters. These dwell within him; since evil, unwholesome states dwell within him, therefore he is called "one with a resident pupil." These assail him; since evil, unwholesome states assail him, therefore he is called "one with a teacher." It is in this way, bhikkhus, that a bhikkhu who has a resident pupil and who has a teacher dwells in suffering, not at ease.
English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.