 पूर्वमेतत्कृतं द्वारं पृथिव्या भुवनस्य च।।सूर्यस्योदयनं चैव पर्वा ह्येषा दिगुच्यते। 
 Here is the entrance for the earth as well as for all the worlds and since the Sun also rises from this place it is called the eastern direction. 