Point Summary
The Real and Immortality
All the essences and their Beings themselves are immortal. Those immortal beings though may or may not have immortal physical bodies.
Typically immortality refers to the extended longevity of the physical body.
Physical immortality is relative, meaning it depends on certain conditions and there are several types and furthermore it can be seen from several different ways. Absolute immortality pertains to the Real Being.
What is Real must be immortal and what is immortal must be real. For something to be real it must always 'be'. It must have been and it must be now and must be in the future. The real is not, what was but is not now. That is, the real is not only what was real in the past but what was real, is real and will be real.
The Absolute is immortal because it is the ultimate reality.
Physical immortality as is taught classically in esotericism is the extension of the lifespan of the physical body of a resurrected Master. As is taught, that extension is not forever, it must be paid for and must be renewed. Master Samael said that the price is sacrifice for humanity.
Reason For
One main reason for immortality is the sacrifice for humanity. The immortal physical body allows a resurrected master to continue his/her service to humanity uninterrupted. An immortal body saves the master from having to be born as a baby and having to go through all the stages of growing up until reaching adulthood.
As the Real Being integrates more and more into the various parts of itself through the levels of creation, it is logical that the Being will integrate into the physical world and body, and it is only the immortal that can make the corruptible incorruptible, and so the Being with no karma and no ego will make the physical of the same nature as it, which is immortal.
Another reason is that for a Monad to return to the Absolute and possess the seed atoms of the four bodies (physical, astral, mental and causal) that Monad must have a physical body. At such a stage where a Monad can enter the absolute such an integration with the Absolute would make the physical body immortal.
Mortality
The reasons for mortality are the fall and the presence of the ego. In the early times of Lemuria human beings were relatively immortal, meaning they lived under the Fulanastaniano principle where the typical lifespan was 1200 years or more.
After the fall, that all changed. Master Samael says because the presence of the ego destroyed the vitality of the physical body drastically reducing the energy and lifespan of the physical body, immortality ended and was replaced with the condition of mortality.
Also because the body that we have now is the mixture of an immortal body and an animal mortal body, the result can not be a mortal body.
Living for too long would cause the ego to develop too much and it would end up in people who do not work on themselves waking up in and for evil (ego). Just imagine the average person instead of living for 80 years, lives for 800 years, and they do not work on themselves. They would end up being really terrible, wouldn't they? It is best that they die and are reborn retarding the development of the ego and subjecting them by force of rebirth to different environments and conditions where they can develop less of the ego.
Our mortality lies precisely in the presence of our ego. With the ego we must be mortal, and turn on the wheel of Samsara.
Practical Aspect
A practical aspect of this topic is to better understand our imminent death and the death of our loved ones.
We and our loved ones have an immortal essence and Being as do we. They will continue but not with the same physical body. If one is awakened one has a kind of immortality where one can continue and particular in a continuous line of consciousness but just through several bodies.
We must awaken and with our consciousness awake we can continue... The continuity and immortality resides precisely in our consciousness.
If we die consciously we can return consciously and not have our flow of consciousness so broken.
End (2756).