Source: here.
oM oM oM hrIM hrIM hrIM shrIM shrIM shrIM 0M aM aM aM hauM hauM hauM haMsaH haMsaH haMsaH oM hrIM shrIM namo viShNave //
The mantra rahasyas:
That great mantra encompasses a series of 3 praNavas. The 3 praNavas are
the AdhAra that is known as the brahman. This is followed by the 3
tArikAs and the 3 anutArikAs which are two wives of viShNu. They are the
supremre states with all things existing in these two shaktis of viShNu.
This sequence represents the primary reality which is the absolute
puruSha, the shAnta and the nAda that manisfest there after. shrI is an
intrinsic part of each stage in the form of time manifesting as nimeSha
and unmesSha.
The praNavas are the primary state of existence the absolute puruSha subtle and with the shakti who is as yet motionless. This is base into which the shakti tArA expands giving rise to the universe. The first manifestation from the puruSha due to the shakti contains both the existing substratum (bhavat) and the manifest existence (bhAva) and tArA resides therein. That state which immediately precedes the expansion of the universe is the inert condition characterized by anutArA; this is state is called shAntA.
The praNava, the brahman, manifests the aprameya (a) the unfolding or the evolution of the universe and after fully expanding the universe becomes extinct into the vyomesha (M). Thus the triad of aM bijas.
In this universe the origin, stable existence and absorbtion is seen to be sUrya, which continuously provides the activity in the universe, which is the hakAra. This combines with the unfolding of the worlds the aprameya (a). The knowers of this see the Ananda (A). This results Ananda results in the udaya of viShNu (u) in the praGYna (U). All merges again in the vyomesha on becoming extinct (M). Thus the bIja hauM emanates.
The manifest universe is pervaded by the prANa hamsaH. Thus is the great
viShNu flanked by his two wives tArA and anutArA, paid obscience. Hence
it is said in the ancient words:
“hrIsh-cha te lakShmIsh-cha patnyau /”
His head is dasha hotar (TA 3.7- prajapatir dasha hotA) ; his limbs are chatur hotar (TA 3.7); his hair, flesh, bones, marrow and blood are panchahotar (TA 3.7); his chest, genitalia and posterior are the ShaD hotar (TA 3.7). His seven prANas regulated by his brain are the sapta hotar (TA 3.7). His handsome glory are dakShiNA (TA 3.10) and the shambhAras are his skeletal articulations (TA 5.2.11). The devapatnyas (TA 3.9) are his blood vessels, the hotR^iNaM hR^idayaM (TA 3.11) is his mind; the puruSha is his consciousness (RV 10.90) and the shrI sUktaM is his shakti (RV Kh 5.87). praNava and tArA bIjas are his secret names, while rudra (TA 4.5.7) and shukra (1.10.1) are is unconcealed names.