Skanda Purana — Brahma Khanda, Shloka 76
नोपतिष्ठेत्तु यः पूर्व्वां नोपास्ते यस्तु पश्चिमाम् । स शूद्रवद्बहिष्कार्यः सर्वस्माद्द्विजकर्मणः
nopatiṣṭhettu yaḥ pūrvvāṃ nopāste yastu paścimām | sa śūdravadbahiṣkāryaḥ sarvasmāddvijakarmaṇaḥ
But one who does not attend the morning sandhyā and does not worship at the evening sandhyā—he is to be excluded like a Śūdra from all duties of the twice-born.
Unspecified (Dharmāraṇyakhaṇḍa normative dharma injunction)
Scene: A didactic scene: a teacher/ācārya admonishes a negligent dvija at dawn/dusk thresholds; the neglected sandhyā shown as fading light, with ritual implements unused.
FAQs
Regular sandhyā observance is treated as foundational to dvija religious discipline.
No tīrtha is mentioned; it is a rule about daily rites.
Do not omit morning and evening sandhyā; neglect is said to disqualify one from dvija rites.