Five thousand years ago, when the Kali-yuga began, so all persons were alarmed: "Now the Kali-yuga is begun. So many catastrophes will come in."
So one instruction is that the earth is addressed "amba." Amba means mother. So the earth is also our mother. There are seven kinds of mother: ādau-mātā guroḥ patnī. Real mother, from whose womb we have taken birth, she is called ādau-mātā, first mother. Then second mother, the guroḥ patnī. Guru means teacher or spiritual master. His wife, she's also . . . actually, according to strict moral instruction . . . why strict? Ordinary. Any woman except his own wife is mother. Any woman. It doesn't matter whether she is elderly or young. No, that is the way. Still in India, any woman by unknown person, he can address any woman "Mother." The first relationship is mother. Now they have introduced "Sister," "Bahinajī." No, that is not Vedic etiquette. No bahinajī. Bahinajī means sister. Mother. Everyone should be addressed. We should learn this. Except one's one wife, all women should be addressed as "Mother." This is civilization. Then there will be no corrupt relation. If you, from the very beginning, you establish your relationship with other women as mother, then there is no question of other relationship.
So here it is instructed. Even the earth is addressed as mother. According to śāstra, Dharitrī is one of the mothers, seven mothers.