Most scientists believe the universe had a beginning. An eternal universe would violate the 2nd Law of Thermodynamics. There is entropy going on. If the universe were infinitely old, total entropy would have already occurred by now. Energy conversions would have already ceased and the mean temperature of the universe would be approaching absolute zero (i.e. a dead universe).
That is correct. So what actually happens is this:
unmanifest manifest unmanifest manifest unmanifest manifest unmanifest....
This cycle is what is eternal. When you/scientists see the universe is going to 'end' owing to laws of thermodynamics and entropy, that is simply the physical energy of the current cycle. What happens after THAT cycle is not being considered, hence that is only a snapshot of the Truth of timeless existence.
Because Brahman is consciousness, awareness, in manifests the universe again, in stages, which expand over a very very long period of time until we come to the galaxy formation stage.
Surprisingly, this is described with amazing accuracy in the Hindu purANas. The eternal cycles of time-space.
Definition: "Reincarnation, a major tenet of Hinduism, is when the soul, which is seen as eternal and part of a spiritual realm, returns to the physical realm in a new body. The belief is that a soul will complete this cycle many times - even hundreds of times, learning new things each time and working through its karma. This cycle of reincarnation is called samsara."
Analysis: From a Biblical standpoint, reincarnation is a false doctrine: “It is appointed for man to die ONCE, and after that to face the judgment” (Hebrews 9:27).
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Reincarnation voids the necessity of Christ for salvation and eternal life. If one can simply 'live again,' then what is the need to believe in Jesus? Therefore, Biblically speaking, the idea of reincarnation is Satanic..
As for savior versus learning life-lessons and transformation of the jivAtmA, why does it have to be mutually exclusive as Christian versus Hindu?
While we learn our life lessons and try to abide by wisdom imparted by the ancients, our IshTaDev or SadGuru can be our savior. The role of the savior is to provide unconditional love and nourishment which makes you strong at heart, ready to take on the challenging spiritual lessons.
Shri KRshNa is my Everything, a super-set of savior, and other forms of the same Brahman also bless the seeking souls, including Jesus by the way.
So your IshTaDev and Guru is Jesus and mine is Shri KRshNa.
The difference is I embrace Jesus except for the "Only Way" part (unless you interpret Jesus == the Principle of SadGuru = anyone who fits that role), whereas many Christians reject Hindu dharma without knowing even the tip of the iceberg floating on the ocean of this eternal Dharma
but that is OK.
Question: How do you know that those Christians who follow Jesus only namesake or half-heartedly, and do not really follow his instructions will not be reborn in the world because their lessons are unfinished ?
but not necessarily go to eternal hell -- since what purpose would that serve? Would you fail a 4th grader eternally because they failed the exam once?
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This summation of common Hindu thought only shows humility: I do not know if I will live up to your expectations completely in this life, O God, but Thy Will be done, and if I do have to come back to this world, please make it so that I will never forget You, and resume where I left off.
Even without this prayer, KRshNa assures Arjun in BG Chapter 6 - Yogis who did not reach the Ultimate State, resume where they left off.
My prayer to Shri KRshNa is to follow the principle of early MS-Windows in case I have to come back ::
"Don't call Me, I'll call you."
So now I have created this hook and can rest in peace because now it is His responsibility to call the hook, because I won't know any better. Who is the "I" in this context? The current left-over pieces of ego just in case it remains.