Canto 1 - Boyhood
Bāla-kāṇḍa
Chapter 58: King Triśaṅku Cursed
Text 1.58.4

अशक्यमिति चोवाच वसिष्ठो भगवानृषिः।
तं वयं वै समाहर्तुं क्रतुं शक्ताः कथं तव॥

aśakyam iti covāca vasiṣṭho bhagavān ṛṣiḥ
taṁ
vayaṁ vai samāhartuṁ kratuṁ śaktāḥ kathaṁ tava

aśakyam iti ca uvāca = has said is impossible [to be executed by him]; vasiṣṭhaḥ bhagavān ṛṣiḥ = the powerful sage Vasiṣṭha; tam = that; vayam vai = we; samāhartum kratum śaktāḥ katham tava = how can be capable of undertaking the sacrifice.

How can we be capable of undertaking your sacrifice that the powerful sage Vasiṣṭha has said is impossible [to be executed by him]?