Smrititattva 1.p2.65

1.p2.65

yogiyājñavalkyaḥ| “hrāsavṛddhī ca satataṃ dinarātryoryathākramam| sandhyāmuhūrttamākhyātā hrāsavṛddhau samāhṛtā”
varāhaḥ “arddhāstamayāt sandhyā vyaktaubhūtā na tārakā yāvat
tejaḥ parihāniruṣā bhānorarddhodayaṃ yāvat”|| ataeva kenāpi
muninā nānādeśīya saṃgrahakāraiśca sandhyāsaṃkrāntitvena viśeṣo
nābhihitaḥ
tadayaṃ saṃkṣepaḥ| dinasaṃkramaṇe kṛtsnaṃ dinaṃ puṇyaṃ ṣaḍaśīti
mukhe ityādyuktaṃ puṇyataraṃ mandā mandākinītyādi rūpeṇa
tricaturādi ghaṭikāḥ puṇyatamāḥ| dinavṛttottarāyaṇādibihita viṃśati daṇḍādīnāṃ rātripraviṣṭabhāgasyāpi puṇyatvaṃ
rātrisaṃkramaṇe tu kalyānnyūna prathamārddhagate taddivasīya śeṣayāmadvayaṃ puṇyam | kālāiyātmaka madhyarātragate taddivasīya titherabhede taddivasīya śeṣayāmadvayaṃ puṇyaṃ bhede tu taddivasīya śeṣayāmadvayaṃ parāddavasauyādyayāmadvayañca puṇyam ubhayadine puṇyakāle'pi pūrvadinākaraṇa eva paradine tadvihitaṃ kāryyam
tithibhedābhedayordakṣiṇāyane taddivasīya śeṣayāmadvayam uttarāyaṇe tu paradivasauyādya yāmadvayaṃ puṇyamiti madhyarātrīyakalottaraśeṣārddharātrasaṃkramaṇamātre tu paradinādya yāmadvayaṃ
puṇyamiti sandhyāsaṃkramaṇe tu dinadaṇḍe dinasya rātridaṇḍe
rātrervyavasthāitiḥ
brahmapurāṇe | “śuklapakṣe tu saptamyāṃ yadā saṃkramate raviḥ
mahājayā tadā proktā saptamī bhāskarapriyā || snānaṃ dānaṃ
tapo homaḥ pitṛdevābhipūjanam | sarvaṃ koṭiguṇaṃ proktaṃ tapanena sahaujasā ||” atra “māsapakṣatithīnāñca nimittācca
sarvaśaḥ” ityanena prāpta tithyullekhe tadviśeṣaṇatvena mahājayetyullekhyaṃ saṃjñā vidheretadeva prayojanaṃ yattayānirdeśa ityuktatvāt