Bhagavatapurana 2.6.19

2.6.19

pādāstrayo bahiścāsann aprajānāṃ ya āśramāḥ /
antastrilokyāstvaparo gṛhamedho 'bṛhadvrataḥ //

19 (Further) the three Asramas or states of life viz those of the perfect Brahmacharin, Vanaprastha and Sanyasin who do not beget children, constitute His three feet which are outside (beyond the three regions); (but) within the these three worlds dwells (remains) the other class consisting of householders who do not observe the great austerity of Brahmacharya (sole devotion to God).