Ramayana
तपस्यता महाबाहो लोकाः वृत्रेण निर्जिताः । बलवान्स हि धर्मात्मा नैनं शक्ष्यामि शासितुम् ॥ 7-84-12 ॥
"'O mighty-armed one, by Vritra, who is practicing austerity, the worlds have been conquered; for he is powerful and righteous, and I shall not be able to subdue him."
english translation