If they do not respect each other, destruction would befall the people. The Brahmana and the Kshatriya are said to be the creators of all men.
विमाननात् तयोरेव प्रजा नश्येयुरेव हि। ब्रह्मक्षत्रं हि सर्वेषां वर्णानां मूलमुच्यते॥