तैत्तिरीयोपनिषद्

Taittiriya Upanishad

Divided into three sections covering education, bliss of Brahman, and tapas-based realization. Contains the convocation address 'satyam vada, dharmam chara' and the Shanti Patha 'saha nau avatu', along with the doctrine of the five sheaths (pancha kosha).