Martinus: Livets Bog, vol. 2, sect. 584

584. That the living being is "immortal" can only confirm the tenth basic element of life's mystery to be of an unshakeable advantage. If the living being were "mortal", it would be identical with a "created thing", for only a "created thing" can be "mortal", in other words "temporal" or "perishable". "Something" which has not been created but all the same exists can never "come into existence", just as it in all eternity "can never cease to remain in existence". It is quite outside the laws of creation. To deny the existence of any such "something" is the same as to deny the one "something" in life which can be called the "creator". It would be the same as to assert that the "created thing" has created itself. It would be to make a house the creator of its builder. And with this we already arrive in the province of abnormality.
In order to be on the firm ground of normality we must therefore recognize such an existing "something" as the master and the source of all things created. It is this reality which looks through our eyes, hears with our ears, speaks with our tongues and thinks with our brain and furthermore whose existence we confirm with the one little word "I" every single time we express anything about ourselves. We say "I run", "I sleep", "I was ill", "I was pleased", "I was lively", "I was healthy" and so on. Therefore we cannot deny its existence without putting a "nothing" in its place. We would then have to say "nothing ran", "nothing sleeps", "nothing was ill", "nothing was pleased" and so on and then be in disharmony with the actual facts, for it must be acknowledged that we do exist and therefore cannot be "nothing" but must necessarily be a "something". Whatever we do, we cannot, in any case whatsoever, exist as the originator of an action or manifestation without being identical with that "something".
To assert that this "something" was only our physical body is no solution to the problem, for that body consists solely of "created" actualities. And as these can exist only on account of a "creative ability" and this again can never in any circumstances be established as self-determined but must always be analogous with an attribute of an existing "something", then we have to place this "something" within a living being as the same as its centre, its true Self, its "I" or that reality which survives, forms and creates the temporal phenomena, organisms and other manifestations present in that same being. To deny the living being's immortality is like denying that created or produced things have a source or a "creator". But such an attitude would be the same as to deny the existence of life itself. An existence without "immortality" or the tenth basic element of life's mystery, cannot possibly be identical with life but would undoubtedly have to be the same as an eternal "nothing".