The first thing is that bhagavān uvāca. These things required for purification. Sattva-saṁśuddhiḥ. The human life is meant for sattva. Sattva. Sattva means existence. We are existing. I am existing; you are existing. But we are sometimes appear to be not existing. That is called death. We, every living entity, we are eternal. That is stated in the Second Chapter, that ajo nityaḥ. . . ajo nitya śāśvataḥ, na hanyate hanyamāne śarīre (BG 2.20). These things required to understand, that "I am a living being—not only I am, everyone. We are eternal, nityaḥ śāśvataḥ." There are so many universities all over the world and so-called scientists and philosophers, but they do not know that we are eternal. Just see their knowledge, advancement of knowledge. Eternal, aja. There is no birth. Na hanyate hanyamāne śarīre (BG 2.20). After this destruction of this body, I am not finished. I still exist.
What is the destruction of this body? Death means it is a machine. It is called machine. Yantrārūḍhāni māyayā (BG 18.61). It is a machine given to me. Just like you take a car. That is a machine. Now some way or other, if the car stops, not working, does it mean that you are finished? No. I can take another car. This is knowledge. But this knowledge is lacking. People are being educated, but they are all rascals because they have not this simple knowledge that ajaḥ śāśvato 'yam, "I am aja." How it is aja, proof? Yes, there is proof. "How I am eternal?" If somebody asks that "How I am. . .?" (aside:) Don't move that body, that. "How I am eternal?" There is proof. And who is giving the proof? Kṛṣṇa, bhagavān uvāca. The highest authority, not ordinary person or any living being—Kṛṣṇa. Kṛṣṇas tu bhagavān svayam (SB 1.3.28). Kṛṣṇa means the Supreme Personality of Godhead. He is saying. He is giving the proof. What is that proof?
- dehino 'smin yathā dehe
- kaumāraṁ yauvanaṁ jarā
- tathā dehāntara-prāptir
- dhīras tatra na muhyati
- (BG 2.13)
Dehinaḥ. I am dehī. Dehī. This is, body is deha, body. But I am not this body. You think over. If you take this finger, you study, am I this finger? No, the conclusion will come: "It is 'my finger', not 'I finger.'" Simply little knowledge required. How? Now, Kṛṣṇa gives this example, that dehinaḥ, asmin dehe yathā dehinaḥ kaumāraṁ yauvanaṁ jarā. He has explained in different ways, but the beginning is this, that this body is changing. You had a small body, baby's body. Where is that body? If I say, "Where is that body?" what you will answer? But you know that "I had a small body." I know. Everyone will know. But where is that body? That body is not existing. I was also young man like you, but now I am an old man. Old man means my body is different—old body. Your body is different. So Kṛṣṇa giving this very nice example: As the baby is changed into a boy, a boy is changed into a youth, a youth is changed into old man, so this changing is going on. But I or you, we know that "I had such body."
I have several times spoken to you that in my. . . when I was about six months old, I remember. I remember I was lying down on my eldest sister's lap, and she was knitting. I still remember it very vividly. And so many things I remember. But where is that body, lying down on the lap of mother or sister? You cannot say. . . Either you say it has grown. . . Grown or not grown. According to medical science, it is not grown; it is changed. The body is changing. Just like in a film spool, you will find so many bodies. One hand is like this, one hand is like this, one hand is like this, and when they are taken together, it moves like this. This is the film. Film means there are different bodies in different position, and when they are taken at once, it. . . likes that it moves. The picture is not moving. Similarly, we are changing of the different body, but it is taking place so quickly and so, I mean, imperceptibly by Kṛṣṇa's energy. The machine is so nice that we are thinking that it is growing. It is not growing—all different bodies, all different, every moment, every second. That is the scientific. The blood corpuscles are changing, and the body is different.
So this is the preliminary knowledge of advancing in spiritual knowledge. You do not know what is spirit - and what is the spiritual knowledge? This is spirit. That spirit is there. Asmin dehe, in this body, there is the spirit soul, and the spirit soul is permanent. The spirit soul is permanent, and it is expressing in different way according to the change of body. Just like this child is now just like ordinary animal. But this body, when he will change, he will express in a different way. He will express in a different way. Similarly, if you get the cat's body, you will express in a different way. If you get a dog's body, you will express in a different way. If you get the body of a tree, that you cannot express. You will have to stand simply. You have to suffer. You cannot protest. Somebody is taking, cutting, take your fruit, cutting your branch, but you cannot protest.