Mahabharata 13.136.22

13.136.22

śmaśāne hyapi tejasvī pāvako naiva duṣyati |
haviryajñeṣu ca vahanbhūya evābhiśobhate || 22 ||

A blazing fire even when it burns on a crematorium, is not regarded as tainted in consequence of the character of the spot whereon it burns. Clarified butter looks beautiful whether kept on the sacrificial altar or in a chamber. So, if a Brahmana be always engaged in evil acts, he is still to be regarded as deserving of honour. Indeed, know that the Brahmana is always a high deity.'"