Chandogya Upanishad
Prapathaka V, Khanda 17
Then he said to Auddâlaka Âruni: 'O Gautama, whom do you meditate on as the Self?' He replied: 'The earth only, venerable king.' He said: 'The Self which you meditate on is the Vaisvânara Self, called Pratishthâ (firm rest). Therefore you stand firm with offspring and cattle.