Skanda Purana — Avanti Khanda, Shloka 21
सन्ध्याहीनोऽशुचिर्नित्यमनर्हः सर्वकर्मसु । यदन्यत्कुरुते किंचिन्न तस्य फलभाग्भवेत्
sandhyāhīno'śucirnityamanarhaḥ sarvakarmasu | yadanyatkurute kiṃcinna tasya phalabhāgbhavet
អ្នកដែលខ្វះពិធីសន្ធ្យា គឺមិនបរិសុទ្ធជានិច្ច និងមិនសមរម្យសម្រាប់កិច្ចពិធីទាំងអស់; ទោះធ្វើអ្វីផ្សេងក៏ដោយ ក៏មិនបានចំណែកផលនៃកិច្ចនោះឡើយ។
Skanda (deduced)
Scene: A cautionary scene: a person attempting offerings while a shadow of impurity clings; beside him, a disciplined practitioner performing sandhyā with clear light—showing ‘fruitless’ vs ‘fruitful’ action.
FAQs
Daily obligatory worship (nitya-karma) sustains purity and makes other religious acts spiritually effective.
No specific site is named; it is a universal dharma rule stated within Revā Khaṇḍa.
Do not omit Sandhyā-vandana; it is prerequisite for the fruit of other rites.