Skanda Purana — Nagara Khanda, Shloka 21
तत्किं ते तपसः शक्त्या ब्राह्मणस्य विचक्षण । अपरं शृणु मे वाक्यं यद्ब्रवीमि परिस्फुटम् । शृण्वतां मुनिवृन्दानां तथान्येषां द्विजोत्तम
tatkiṃ te tapasaḥ śaktyā brāhmaṇasya vicakṣaṇa | aparaṃ śṛṇu me vākyaṃ yadbravīmi parisphuṭam | śṛṇvatāṃ munivṛndānāṃ tathānyeṣāṃ dvijottama
噢明辨的婆罗门，你苦行之力又有何用？如今且听我另一番话，我将说得分明透彻——当众仙贤与他人皆在聆听之时，噢最胜的二生者。
Triśaṅku (continued address to Vasiṣṭha)
Listener: Vasiṣṭha (and implicitly the assembled sages)
Scene: Triśaṅku speaks loudly, turning slightly toward the gathered sages as if to shame Vasiṣṭha; Vasiṣṭha remains composed; sages react with mixed concern and silence.
FAQs
Spiritual power is questioned when it is not aligned with right action; public dharma-debate is framed as taking place before a community of sages.
No tīrtha is named in this verse.
No direct prescription; the verse challenges the efficacy of tapas and introduces a further demand/argument.