In the Bhagavad-gītā it is clearly explained that there are three kinds of activities according to the different modes of nature: the activities of goodness, of passion and of ignorance. Similarly, there are three kinds of eatables also: eatables in goodness, passion and ignorance. All of this is clearly described, and if we properly utilize the instructions of Bhagavad-gītā, then our whole life will become purified, and ultimately we will be able to reach the destination which is beyond this material sky. (BG 15.6)
That destination is called the sanātana sky, the eternal, spiritual sky. In this material world we find that everything is temporary. It comes into being, stays for some time, produces some by-products, dwindles and then vanishes.