timeless existence vs timelessness

timeless existence and timelessness both are nouns.

Word	Noun	Adjective	Verb	Adverb
timeless existence	Yes	No	No	No
timelessness	Yes	No	No	No

As nouns, timeless existence and timelessness are synonyms defined as:

timeless existence and timelessness: a state of eternal existence believed in some religions to characterize the afterlife

Other synonyms of timeless existence include eternity.

timeless existence (noun)	timelessness (noun)
a state of eternal existence believed in some religions to characterize the afterlife	The property of not being restricted to a particular time or date.
	a state of eternal existence believed in some religions to characterize the afterlife