the mundane world is never eternal. there is, however, a trade off between its observed latent decay and generation.
Nevertheless, we can search for the material work of the eternity and find out Who is the real cause of the existences, material and spiritual.
our philosophical theories are conceptualized within the limits of space and time relation. we can never do the analysis beyond the logic (based on analogies and memorizing).
The material life (existence) is cyclic, however, the spiritual existence is beyond any time frame of observation. The material existence is a work of the spiritual cause. the spiritual cause has no direct relationship with the material cause and the supreme spiritual cause is the cause of all the causes, in material and within spiritual existence.
"teshaam satat yuktanaam bhajtaam pritipurvakam, dadaami budhhiyogam tam yen maam upayanti te."
since, every work has its cause. the material logic to understand something which is beyond time domain is also beyond understanding the cause of the work. so, seems illogical !