The Upanishads, Part 1 (SBE01), by Max Müller, , at sacred-texts.com
1. Then he said to Budila Âsvatarâsvi, 'O Vaiyâghrapadya, whom do you meditate on as the Self?' He replied: 'Water only, venerable king.' He said;
[paragraph continues] 'The Self which you meditate on is the Vaisvânara Self, called Rayi (wealth). Therefore are you wealthy and flourishing.
2. 'You eat food and see your desire, and whoever thus meditates on that Vaisvânara Self, eats food and sees his desire, and has Vedic glory in his house.
'That, however, is but the bladder of the Self, and your bladder would have burst, if you had not come to me.'