Teachings from Taittiriya Upanishad

In the beginning all this was nonexistent. From it was born what exists. That created Itself by Itself; therefore It is called the self-made.

That which is self-made is flavor; for truly, on obtaining the flavor one becomes blissful.

Who could direct the prana and the apana if this Bliss did not exist in the akasa? Brahman verily exists because it alone bestows bliss.

When a man finds fearless support in that which is invisible, incorporeal, indefinable and supportless, he has then obtained fearlessness.

If he makes the slightest differentiation in It, there is fear for him. That becomes fear for the knower who does not reflect.

That One who is Self-existent is verily Joy, Bliss, and Supreme Happiness. Who would have lived and breathed had not this Infinite Bliss existed? This verily is that which bestows bliss—the highest happiness.

Taittiriya Upanishad