KathaUpanishad

According to Vishnu Purana II:8:97 Brahma-loka which lasts till the great dissolution of the
universe is called “immortality” . True “immortality” means freedom from the cycle of birth and
death in other words – liberation from the cycle of samsāra.
Therefore the meaning can be that the enlightened one who dies with the mind focussed in the
heart chakra ascends to the sahasrara chakra and then into the Brahma-loka or realm of
Brahmā. There one remains until the great dissolution and is then reborn with the next cycle of
projection. Or on the other hand it can mean that after remaining in Brahmā-loka until the end of
the cycle one then attains true immortality.
aṅgu̍ ṣṭha mātraḥ pu̱ ruṣo̍ 'ntarātmā sadā̍ janāṉām hṛ̱ daye̍ sanniviṣṭaḥ |
taṁ svāc cha̍rīrāt pra̱vṛhe̍ n muñjā̍d iveṣīkāṁ dhairye̱ ṇa |
taṁ vidyāc chuḵram a̱ mṛta̱ ṁ taṁ vidyāc chuḵram a̱ mṛta̍ m iti || 17 ||
aṅguṣṭha mātraḥ puruṣaḥ = the Person the size of a thumb
antarātmā = witin one's very own Self
sadā = always
janānām hṛdaye sanniviṣṭaḥ = seated in the hearts of all people
taṁ = him
pravṛhet = one should draw out, separate
svāt śarīrāt = from one's own body
iṣīkāṁ iva muñjāt = like a stalk from within the munja grass
dhairyeṇa = unerringly, steadily
taṁ = that separated consciousness
vidyāt = one should know
śukram amṛtaṁ = as pure and immortal
taṁ vidyāt śukram amṛtam iti = the repetion indicates the end of the teaching.
The Purusha, not larger than a thumb, the inner Self, always dwells in the hearts of men.
Let a man separate Him from his body with steadiness, as one separates the tender stalk
from a blade of grass. Let him know that Self as the Bright, as the Immortal−yea, as the
Bright, as the Immortal.
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