Skanda Purana — Mahesvara Khanda, Shloka 156
ते तृप्तास्तर्पयन्त्यस्य पूर्वजान्यत्र संस्थितान् । एवं स्वानां चोपतिष्ठेच्छ्राद्धं यच्छंति ते वरान्
te tṛptāstarpayantyasya pūrvajānyatra saṃsthitān | evaṃ svānāṃ copatiṣṭhecchrāddhaṃ yacchaṃti te varān
彼らが満ち足りると、今度はそれぞれの界に住するその者の祖霊をも満たす。ゆえに自らの家系のため、法にかなってシュラーダ（Śrāddha）を勤めるべきである。そうすれば祖霊は恩寵を授ける。
Mahākāla
Listener: a king
Scene: A layered ancestral chain: the performer’s offering rises to satisfied pitṛs, who then send nourishment further back to earlier forebears; finally blessings descend as light upon the family, symbolizing boons granted.
FAQs
Śrāddha works through a chain of satisfaction: higher Pitṛs become pleased and nourish earlier ancestors, culminating in blessings for the performer.
No site is specified; the emphasis is on the ritual’s intergenerational efficacy.
One should perform Śrāddha for one’s own ancestral line, with tarpaṇa (satiating offerings) as the operative principle.