In the earlier sloka Lord Krishna explained about the kshara akshara purushas ,that which are mutable and immutable. In continuation, in this sloka he explains about uttama purusha.
15.17 – Uttama purusha anyah paramah iti udahrtah
Yo loka traya avisya bibharti avyayah ishwarah
Meaning of words:
Uttama purusha – the supreme person
Anyah – different in characteristics
Udahrtah – as per Upanishads
Yo – who
Loka –traya – the three worlds
Avisya – permeates
Bibharti – upholds
Avyaya – imperishable
Ishwarah – god
Meaning of sloka
The supreme purusha is different from the kshara(mutable) and akshara(immutable) purushas. He is the supreme lord spoken about in the Upanishads. He permeates the three lokas and also sustains them. He is the imperishable lord ishwarah.
Lord Krishna here mentions about the Uttama purusha or the pure consciousness the Upanishads talk about. This uttama purusha is entirely different from the kshara and akshara purusha. As we have seen in the earlier sloka kshara purusha is the mutable entity which changes and akshara purusha is immutable and is the consciousness present in every living being. So the question may arise as to what is the difference between the akshara purusha and uttama purusha. Akshara purusha is also called kutastha and uttama purusha is called brahman , about whom the Upanishads talk about. Both kutastha and brahman are the same as the pot space and the space outside the pot are the same. They are different with respect to the limitations. Kutastha is limited to the body adjuncts, as the pot space is limited by the pot, as the room space is limited by the room. Thus brahman is different from both kutastha and the kshara purusha or the changing body.
The supreme being or brahman is present in all the three lokas – bhuh (Earth), bhuvah (intermediate space) and the svah( the heaven) . He is the creator of the whole world and sustains the world. He is the creator and protector of the universe. He is of the nature of sat chit ananda.
Thus Lord Krishna talks about 3 purushas the kshara or the changing body, akshara or the immutable or kutastha ,which has body limitations and the uttama purusha which is of the nature of sat chit ananda, the all pervading brahman , not limited by time and space. Once the seeker goes beyond the adjuncts of the body , the kutastha becomes one with the Brahman , as when the pot is broken down , or the walls of the room are broken down, the room space or pot space becomes one with the space outside. This state of realization a seeker should strive for.