Smrititattva 1.p2.31

1.p2.31

sārthakatvāya nimittatvena māsapakṣatithyullekhānantaraṃ mahāvāruṇī mahāmahāvāruṇyāvullekhanīye śrāddhe pārvvaṇādi saṃjñollekhavat paurṇamāsyamāvāsyayoḥ pakṣollekhavacca | “māsapakṣatithīnāñca nimittānāñca sarvaśaḥ | ullekhanamakurvvāṇo na
tasya phalabhāgbhavet” || iti vacanāt | tena caitre māsi
kṛṣṇapakṣe trayodaśyāṃ tithau mahāvāruṇyāṃ mahāmahāvāruṇyāṃ
yathāyathaṃ prayojyam | vārastu sūryyodayādudayāntaraṃ yāvat
tathā ca sūryyasiddhāntaḥ “sūtakādi paricchedo dinamāsābdapāstathā | madhyamagrahabhuktiśca sāvanena prakīrttitāḥ | udayādudayādbhānorbhauma sāvana vāsarāḥ” || dinādhipasya ravyāderbhāṃgyaṃ dinaṃ vārarūpaṃ sāvanagaṇanenoktaṃ bhaumeti pitrādidinavyāvṛttyarthaṃ kaurma pādmayoḥ “dvau tiṣyantāvikavāre yatna
syāt sa dinakṣayaḥ” || vaśiṣṭhaḥ | “ekasmin sāvane tvaṅgi
tithīnāṃ tritayaṃ yadā | tadā dinakṣayaḥ proktastatra sāhastrikaṃ
phalam” || ityetayorvacanayorekavākyatayāpi tathāvagamyate
rekhāpūrvāparayorityādikantu jyotiḥśāstroktaṃ kālahorādijñānārthamiti | atra “saṃkrāntiṣu vyatīpāte grahaṇe candrasūryyayoḥ | puṣye snātvā ca gaṅgāyāṃ kulakoṭauḥ samuddharet”
iti brahmāṇḍa purāṇāt grahaṇamātre trikoṭi kuloddharaṇavidhānāt tato'dhikeṣu vāruṇyādiṣūttarottaraguruṣu mahāmahāvāruṇyāmapi yat trikoṭi kuloddharaṇamuktaṃ taduddharaṇagatatāratamyenāviruddham | “yaṃ yaṃ kratumadhīte ca tasya tasyāpnuyāt phalam”
iti yājñavalkyoktādhyayanāt yathā tattadyāgakaraṇe'dhika phalam
ataeva śiṣṭānāmādaro'pi tatheti | na cātra “snānaṃ kurvvanti