(JAYA) Mahabharata, Bhisma Parva (6th of 18 books), Chapters 23-40:

Srimad Bhagavad Gita As It Is small and large

Introduction

Sanatana Dharma means that which sustains oneself eternally = Krishna Consciousness (Pure Devotional Service aka Bhakti Yoga).

The purusartha called Dharma means that which sustains the current temporary body, check the diverse birth charts of the humans in Kali Yuga and then check the chart when the Supreme Personality of Godhead appears.

A society which adhers to Krishna Consciousness with Brahminical qualities and Cow protection as its basis is called a society of Aryans (those who follow the Vedas and protect and serve the Brahmanas and Cows aka the Arya-samaj