The closest belief system to this on Earth must be Nirvana of the Buddhists I think. Pretty much like saying Amida untill you've acheived your aim. Though, Nirvana is moreorless amalgamating yourself in with God, CHIM here is doing so but retaining yourself. Yeah, I see what implies; freaking hard, that's what.
Er, no. That emphasis on 'I' in CHIM is in many ways the antithesis of Buddhist
nirvana, which is both non-theist and involves no-self. Through that lens, the 'I' clung to in CHIM is an illusion, and as such the person who has achieved CHIM is, by virtue of their immense certainty and attachment to the self, farther from
nirvana than anyone could possibly be.
But it's all quite different. TES cosmology is very,
very dualistic. Comparisons to Buddhism and other native Indian philosophies are always going to fall down there.