In the Bhagavad Gita there is the description of Him where Sri Krishna says: “I am the one on whom everything depends, but I do not depend on them”: that is the description of “Sat”; “They all depend on Me, but I do not depend on them”. There is even a more drastic statement in the Bhagavad Gita, which shall come after this first block of 6 chapters are over, then 7th, 8th , 9th chapters are the chapters of full Knowledge, where all these things are expounded, and there you will find the description where Sri Krishna says: “They are in Me, I am not in them”, just as He says: “They all depend on Me, but I do not depend on them”, similarly He says, “They are in Me, but I am not in them”. Now, in a certain sense this is a very surprising statement: “They are in Me, but I am not in them”. So, there is a Reality such that transcends any idea of dependence, you might say: totally independent Reality. In Latin it is called: ‘Sui Generis’. One, whose origin is within oneself, does not depend upon somebody else at all.
So, this is what we call “Sat”. In the Veda, the Reality is described as Sat, basically. The famous sentence of the Rig–Veda: ekaṁ sad (viprā) bahudhā vadanti, (I, 164, 46), “Reality is one but it is variously described”; ekaṁ sad bahudhā vadanti: it is the description of the Sat. There is a Reality in comparison with which everything else is asat, it looks non–existent: this is also an extreme statement. When you are in the presence of the supreme Reality everything else looks as if it is unreal. When you have drunk the amṛta, ‘nectar’, then every other drink is absolutely tasteless, almost nothing. Now, such are the descriptions, which we find of that Reality, Sat, without which all this, unless you are in it, unless you have discovered that Sat, there is no final resting place.
In fact all solutions are resting places. And when there is a problem, it means that resting place is gone, so we want a solution, and we want to have resting place. And all resting places, so called resting places are only temporary stations. They may give you as if it is a destination, but they are all stations, until you reach that point which is the…the “Sat”. And the Bhagavad Gita wants to stress to Arjuna, because he is in a state of a problem, and Sri Krishna wants to tell Arjuna that all his problems arise because he does not refer to Sat. If you read the whole argument of Arjuna, there is no reference to Sat at all, and that is why Sri Krishna says that, “You speak like a wise man, but you are not wise, because wise people start with “Sat”, that which is eternal”. That is the very starting point as I have said at that time, a big “dong!” with which the Gita starts is a statement of that which is eternal, that which is irreducible, that which is essence, that which does not die, that which is immortal. It is with that, that the whole Bhagavad Gita starts. So, you might say, He starts with the Sat.