..jai jai Maa!
bless you Rising Spirit..
and thank you zhoro for bringing us back to advaitan focus..as always 
Tattvamasi, apologies for the delay..
i thought i'd discuss a little some of the passages from the Katha Upanishad which you posted, thank you..
a lot more can be said though..
(it's also worth noting that different translations bring out slightly different expressions, of the same thing)
..here we have the core principle of the transient nature of pleasures in life vs the unending bliss of the Parmamatman..the omniscient consciousness..
i think an important point to make here is that the Vedantan view of morality, or sin, is quite different to the Judeo-Christian..many westerners reject concepts of renunciation in Vedanta, based on a jaded Christian concept of sin as doing something wrong, and of subsequent punishment..how can pleasurable acts of nature be 'wrong' when they are part of creation?
the Vedanta view (which parallels the Buddhist) is simply that you have a choice..obsession and addiction to transient acts of pleasure will lead one away from the realisation of the absolute, and hence away from lasting happiness..the constant need to satisfy the senses is a very small way of living life..whereas the absorption of the mind into the Atman, and the focus on actions which honour the 'deity' are a bigger picture, leading to a sense of completeness..identifying simply with the small self, the body/mind ego, is ignorance..
..samsara..the endless cycles of death and rebirth (but of what?)
..the Self, the Purusha, has no attributes..it is 'stainless'..and completely transcendental..without beginning..
..the Vedanta guidelines, or traditional 'laws', for how to conduct oneself are called Sastra (Shastra) .. (or the Yamas, as given by the supreme goddess)
..renunciation does not mean, in Vedanta, that one should give up one's career, or cease action, or not be engaged in life..it means not to be lead blindly by desire..it means to have control of one's desires..and to ultimately simply desire truth, of the Realm of the Self..
D. Krishna Ayyar wrote:
hence:
..the Bhagavad Gita, the Upanishads, and Adi Shankaracharya tells us that Karma-Yoga is required to attain the Knowledge yoga..positive actions are required..
but also Brahman, or That, or the transcendental goddess (or the like) cannot be simply realised by scholarship, intellect, and yoga and dharma (good actions), though these are all said to be required..and a teacher is said to help
..It must ultimately be understood directly..
..the unending sound..
ॐ