Flesh cannot be had from grass or wood or stone. Unless a living creature is killed it cannot be procured. Hence is the fault in eating flesh.
न हि मांसं तृणात् काष्ठादुपलाद् वापि जायते। हत्वा जन्तुं ततो मांसं तस्माद् दोषस्तु भक्षणे॥