A simple translation of the Upanishad containing the original text in Devanagari, transliteration of each shloka, and word-for-word English rendering followed by a running translation and notes based on Shankaracharya's commentary.
Anything that is secret and mysterious in these systems of yoga should be at once rejected. The best guide in life is strength. In religion, as in all other matters, discard everything that weakens you, have nothing to do with it.
-Swami Vivekananda