The Upanishads contemplate a "Theory of Truth" which suggests that the Truth can be attained through "Path of Renunciation". Once enlightenment is attained, the truth is realized and it can be enjoyed by the human mind even after renunciation of all material possessions and distractions.
The idea does not have anything controversial about it. Many religions tell their respective subjects to renounce their worldly possessions so that their souls can be released from this world and unite with God.
Why do they all do so? Maybe this is due to some common trait that we, as Homo Sapiens species, all share. The trait of escapism. A hidden urge to escape. The Abrahamic religions preach that their souls would go to heaven or hell based on a divine judgement. Only the worthy go to Heaven and be with God, in a way escape the worldly bondage of our physical world. It is like severing that binding cord and be with God. One with Him. They have different versions of it in their textbooks but this is essentially what they teach.
Eastern religions, generally have a circular view of a soul's lifeline, preaching the birth-rebirth concept. It is through one's deeds that the soul gets appraised at regular intervals. Which is quite like the annual performance appraisal cycle, a famous event in the corporate world. Therefore, through satisfactory behaviour one's soul can achieve Moksha from our materiality to eternal sublimity and become one with God.
What makes me curious is, why do we all want to escape? Why is it that we don't have any major religion that believes that our souls shouldn't escape the material world? Why can't it be that we never escape? that there is no escape, or nowhere to escape! The phenomenon of death is a strong influencer behind this mindset. Of course, in those formative years of human being's major religions till date, death would be as incomprehensible to their minds as it is to ours even today. The affection for a person would have led it to establish in the minds of his close ones that he were still alive, in some other, ethereal form, in a state higher than us, in a state of bliss, with God (maybe that is the reason behind the invention of the concept of soul. And since our souls are eternal, in a way we are eternal. But it is also a truism that our bodies are going to stop functioning someday), our souls would be judged/appraised and ultimately we may get the chance to be in that higher Godly state of eternal bliss.
For want of a guide, ancient Hindu scriptures developed a philosophy to achieve the soul's union with God. Interestingly, this philosophy contains a theory of sheaths, or facets of our personalities. The topmost sheath, the highest of them all is the Bliss sheath. Essentially, it is a state of ignorance. Ignorance of the world and its attachments; attachments even to one's body. Ignorance here means detachment, and when one is detached completely from the world, he has escaped the world. Escapism again.
