Tukaram, Poem 2473

A crow knows no mercy or gratitude; it is dark without and full of nastiness within. Even so the life of the wicked is unholy; dirty and ungracious are the words he talks. Though you cook a bitter gourd and season it, it causes pain in the head of one who tastes it. Tuka says, A snake will not lay aside his poison; he thinks highly in his mind of his own vicious qualities.