Adhyaya 89: शौचाचारलक्षणम् — सदाचार, भैक्ष्यचर्या, प्रायश्चित्त, द्रव्यशुद्धि, आशौच-निर्णय
जनयत्यङ्गना यस्मान् न गच्छेत्सर्वयत्नतः चतुर्दश्यां यदा गच्छेत् सा पुत्रजननी भवेत्
janayatyaṅganā yasmān na gacchetsarvayatnataḥ caturdaśyāṃ yadā gacchet sā putrajananī bhavet
Puesto que se dice que ese tiempo engendra un resultado determinado, la mujer debe, con todo empeño, evitar la unión en ese momento inauspicioso. Pero si se une en el decimocuarto día lunar, se convierte en madre de un hijo varón.
Suta Goswami (narrating traditional dharma/vrata-related guidance within the Linga Purana discourse)
It links household discipline (niyama) with sacred calendrical observance; Chaturdaśī is strongly associated with Shiva-vratas, and regulating conduct on tithis is presented as supportive of purity and merit that undergird Shiva-bhakti.
Indirectly: Shiva-tattva is approached through niyama and tithi-based vrata culture—training the pashu (bound soul) to restrain impulses (pāśa) and align life with dharma, which is ultimately upheld by Pati, Lord Shiva.
A vrata-oriented niyama: observing lunar days (especially Chaturdaśī) and practicing restraint/regulated conduct as part of Shaiva household discipline rather than a technical Pāśupata yoga mudrā or āsana.