Mahabharata 1.9.20

1.9.20

sa kadācidvanaṃ vipro rururabhyāgamanmahat |
śayānaṃ tatra cāpaśyaḍḍuṇḍubhaṃ vayasānvitam || 20 ||

"One day, O Brahmana, Ruru entered an extensive forest. And there he saw an old serpent of the Dundubha species lying stretched on the ground. And Ruru thereupon lifted up in anger his staff, even like to the staff of Death, for the purpose of killing it. Then the Dundubha, addressing Ruru, said, 'I have done thee no harm, O Brahmana! Then wherefore wilt thou slay me in anger?'"