Chāndogya Upaniṣad 3.7.4

3.7.4

sa yāvad ādityaḥ purastād udetā paścād astam etā dvis tāvad dakṣiṇata udetottarato 'stam etā rudrāṇām eva tāvad ādhipatyaṃ svārājyaṃ paryetā \\307.4\

4. As long as the sun shall rise in the east and set in the west, twice so long will it rise in the south and set in the north, and just that long will he compass the overlordship and the chief sovereignty of the Rudras.