Āpastambagṛhyasūtra with Haradatta's Anākulāvṛtti and Sudarśana's Gṛhyatātparyadarśanavyākhyā (with commentary) · Chapter 63

iti śrīsudarśanācāryaviracite gṛhyatātparyadarśane viṃśaḥ khaṇḍaḥ //
samāptassaptamaśca paṭalaḥ //
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athāṣṭamaḥ paṭalaḥ //
ekaviṃśaḥ khaṇḍaḥ /
punarapi pākayajñāntaraṃ puruṣatrayasampradānakaṃ tādṛśānāmaṣṭakādīnāṃ prakṛtibhūtaṃ māsiśrāddhasaṃjñikaṃ pitryaṃ karmopadiśyate--
22 māsiśrāddhaprakaraṇam -
1 māsi śrāddhakālaḥ /
māsi śrāddhasyāparapakṣe yathopadeśaṃ kālāḥ // Ā
(pa.8.khaṃ.,21-1)
COMMENTARIES:
ĀpGs-Anā_21.1:
māsiśrāddhaṃ nāma pitryaṃ karma māsi māsi kartavyam /
tatra ye 'parapakṣe kālaviśeṣāḥ sāmayācārikeṣūpaṣṭāḥ"prathame 'hanikriyamāṇe (āpa.dha.2-16-8) ityādayaḥ aparapakṣasyāparāhṇaḥ śreyā"(āpa.śrau.2-16-4)niti ca te sarve yathopadeśaṃ yathā tatropadiṣṭāḥ tathaiva māsi māsi pratyetavyāḥ /
yadyapi te viśeṣāḥ tasmādeva vacanāt siddhāḥ tathāpi tasya karmaṇaḥ prayogavidhānamita uttaraṃ kriyata iti jñāpanārthamidaṃ vacanam /
anyathā jñāpayeta śucīn mantravataḥ ityādi kasmin karmaṇi vidhīyata iti /
evaṃ tarhi māsiśrāddhasyaitadevādhikārārthamastu /
tasmādidamasya prayojanam-māsaparimāṇamanapekṣyāparapakṣavaśaena parvakālā yathepadeśaṃ yathā syuriti /
tena pūrvasmin pakṣe pañcadaśyāmakṛtaśrāddhasyāparasmin pakṣe prathamādiṣu sarvāsu tithiṣu kriyābhavati tattatkā-masya