When our soul leaves our physical body, our body ceases to function and this stage is called death. Therefore death is related to the gross body. But our soul continues to exist. Depending upon our karmic account, the soul enters a new form and born again. But what happens to the atman or Brahman whom we say exist in the form of a self illuminating fire in the heart chakra. Atma remains everywhere and in order to realize the atman, we say it is in the form of OM or in the form of light, etc. In order to gain some knowledge about the Brahman, it is given some form or other. These attributes to Brahman become a necessity to make us understand what it is. Without the Brahman the other two, soul and physical body cannot exist. We can even say that the Brahman creates bondage between soul and the body. Even this description also assigns attributes to the Brahman. This description with attributes is needed to emphasize that creation is not possible without Brahman. There is a famous saying in Katha Upanishad. “Anoraniyan mahato mahiyan atma” This means atma is smaller than the smallest and bigger than the biggest.
The Upanishad points that the atma is posited in the cave which we have discussed earlier. Locating this cave and exploring it is called self-realization. This is possible only if you do not have attachments, desires etc. Such a person is free from worries and fears. This is mainly because he knows that the body is not everything and the sufferings are only to the body and not to the atma. He knows that his body is different from atma. Atma cannot suffer as it is beyond sufferings, miseries etc. Atma is not associating with any of the activities and is merely witnessing the activities. So, only such a person can have knowledge about the Brahman. He too has knowledge about the Brahman and not yet realised the Brahman. When the Brahman exists everywhere, why then he is identified as light in a cave. This has been answered earlier. The reason is simple. We do not have sufficient knowledge about Brahman. In order to give us some knowledge about Brahman the terms such as light and cave are used. These descriptions are necessary for our knowledge. But Brahman can be realized only if you have desire, inclination, craving, dedication to realise Him and above all by internal exploration.
The Supreme Self can be realized only through knowledge. Yama explains the basic requirements to attain knowledge. The foremost requirement is to abstain from performing evil deeds. There are many scriptures that list out the evil deeds to be avoided. I personally feel that your mind is the best judge to determine which is evil and which is not. The second requirement is to abstain from sensual pleasures. Again I personally feel that sensual pleasure is a biological necessity and abstaining from it is against the law of nature. At the same time too much of sensual pleasure is definitely not good for the spiritual progress. Instead of abstaining, restrain. The third qualification is not to make your mind as your master and instead you become master for your mind. When you learn to keep your mind under your control, there is no need to discuss about the first two. Only when your mind wanders, you do not have the time to explore within, as your mind keeps you busy with external objects. Your mind should be trained in such a way that instead of listening to the beating of the drum outside, listen to the sound of OM inside.