The Great Epic of the Bhārata dynasty 1.188.11

1.188.11

na tu dharmasya sūkṣmatvādgatiṃ vidmaḥ kathaṃcana |
adharmo dharma iti vā vyavasāyo na śakyate || 11 ||

"After Drupada had ceased, Dhrishtadyumna spoke, saying 'O bull amongst Brahmanas, O thou of ascetic wealth, how can, O Brahmana, the elder brother, if he is of a good disposition, approach the wife of his younger brother? The ways of morality are ever subtle, and, therefore, we know them not. We cannot, therefore, say what is conformable to morality and what not. We cannot do such a deed, therefore, with a safe conscience. Indeed, O Brahmana, I cannot say, 'Let Draupadi become the common wife of five brothers.'