SB 10.87.18
udaram upasate ya rsi-vartmasu kurpa-drsah
parisara-paddhatim hrdayam arunayo daharam
tata udagad ananta tava dhama sirah paramam
punar iha yat sametya na patanti krtanta-mukhe
Translation:
Among the followers of the methods set forth by great sages, those with less refined vision worship the Supreme as present in the region of the abdomen, while the Arunis worship Him as present in the heart, in the subtle center from which all the pranic channels emanate. From there, O unlimited Lord, these worshipers raise their consciousness upward to the top of the head, where they can perceive You directly. Then, passing through the top of the head toward the supreme destination, they reach that place from which they will never again fall to this world, into the mouth of death.
Purport:
Here the srutis who teach meditational yoga glorify the Personality of Godhead. The various processes of yoga are for the most part gradual and full of opportunities for distraction. Authentic methods of yoga, nonetheless, all aim at meditation on the Supersoul (Paramatma), whose primary residence is in the region of the heart, alongside the jiva soul. This manifestation of Paramatma in the heart is very subtle and difficult to perceive (daharam), and thus only advanced yogis can realize Him there.
Neophyte meditators often practice focusing on the Supersoul’s secondary presence in one of the lower centers of vital energy, such as the muladhara-cakra, at the base of the spine, the svadhisthana-cakra, in the area of the navel, or the manipura-cakra, in the abdomen. Lord Krsna refers to His expansion as Paramatma in the abdominal cakra as follows:
aham vaisvanaro bhutva
praninam deham asthitah
pranapana-samayuktah
pacamy annam catur-vidham
“I am the fire of digestion in the bodies of all living entities, and I join with the air of life, outgoing and incoming, to digest the four kinds of food.” (Bg. 15.14) Lord Vaisvanara presides over digestion and in general bestows the capacity of mobility on animals, humans and demigods. In the judgment of the srutis speaking this verse, those who limit their meditation to this form of the Lord are less intelligent, kurpa-drsah, meaning literally “having eyes clouded by dust.”
The superior yogis known as Arunis, on the other hand, worship the Supersoul in His form as the indwelling companion of the jiva in the heart, the Lord who endows His dependent with the power of knowledge and inspires him with all varieties of practical intelligence. And just as the physical heart is the center of blood circulation, so the subtle heartcakra is the crossroads of numerous channels of prana, called nadis, which extend outward to all parts of the body. When these passageways have been sufficiently purified, the Aruni yogis can leave the heart region and go upward to the cakra at the roof of the brain. Yogis who leave their bodies through this cakra, the brahma-randhra, go directly to the kingdom of God, from which they need never return to be reborn. Thus even the unsure process of meditational yoga can bear the fruit of pure devotion if it is followed perfectly.
Srila Visvanatha Cakravarti Thakura cites several sruti-mantras that echo the words of this verse: udaram brahmeti sarkaraksa upasate hrdayam brahmeti arunayo brahma haivaita ita urdhvam tv evodasarpat tac-chiro ’srayate. “Those whose vision is clouded identify Brahman with the abdomen, while the Arunis worship Brahman in the heart. One who is truly Brahman-realized travels upward from the heart to take shelter of the Lord who is manifested at the top of the head.”
satam caika ca hrdayasya nadyas
tasam murdhanam abhinihsrtaika
tayordhvam ayann amrtatvam eti
visvann anya utkramane bhavanti
“There are one hundred and one subtle pranic channels emanating from the heart. One of these — the susumna — extends to the top of the head. By passing up through this channel, one transcends death. The other channels lead in all directions, to various kinds of rebirth.” (Chandogya Upanisad 8.6.6)
The Upanisads refer repeatedly to the indwelling Paramatma. Sri Svetasvatara Upanisad (3.12-13) describes Him as follows:
mahan prabhur vai purusah
sattvasyaisa pravartakah
su-nirmalam imam praptim
isano jyotir avyayah
angustha-matrah puruso ’ntar-atma
sada jananam hrdaye sannivistah
hrda manisa manasabhiklpto
ya etad vidur amrtas te bhavanti
“The Supreme Personality of Godhead becomes the Purusa to initiate the expansion of this cosmos. He is the perfectly pure goal that yogis strive to reach, the effulgent and infallible ultimate controller. Measuring the size of a thumb, the Purusa is always present as the Supersoul within the hearts of all living beings. By exercising proper intelligence, one can realize Him within the heart; those who learn this method will gain immortality.”
In conclusion, Srila Sridhara Svami prays:
udaradisu yah pumsam
cintito muni-vartmabhih
hanti mrtyu-bhayam devo
hrd-gatam tam upasmahe
“Let us worship the Supreme Lord, who resides in the heart. When mortal beings think of Him by the standard procedures established by great sages, meditating upon Him in His expansions in the abdomen and other regions of the body, the Lord reciprocates by destroying all fear of death.”