Bhr.gu Valli
This Valli describes how son of Varuna(The Water God) Bhr.gu obtained realization of Brahman through repeated Tapas under his fathers guidance.
Rest of the part of Valli describes greatness of donating food, that is feeding the hungry. It also emphasises on greatness of Food. It says that since food is support of all life, food should not be insulted, food should not be declined.
Read more about this topic: Taittiriya Upanishad