An empty mind can be a boon or bane for an individual and this depends upon what is stored in the subconscious mind of the person and whether a person knows how to deal with them. If there are a lot of incidents which are associated with fear in the subconscious mind then invariably it is the tendency of an empty mind to bring them up. If we know how to deal with them and eventually heal them then this healing experience can actually turn out to be quite rewarding but if we are not aware of the techniques then we may have feelings of anxiety and restlessness in which we may take destructive steps.
Tendencies Determine Fears
A person is born with certain tendencies, be it tendency towards learning music or aggression or high sexual appetite etc. There is nothing wrong with any of them as it depends upon the DNA of the person. But the problem is that there is a small subset of tendencies which a society, at a particular point in time, considers acceptable. Tendency towards aggression may have been accepted and even celebrated 500 years ago but in today's world, in most societies, it is condemned. Similarly tendency towards learning music may be celebrated in today's society but condemned in earlier society. This causes people with tendencies not acceptable in their respective society, to invariably face incidents in which they fear for their safety and if they don't have a broader perspective then it may even lead them to hold feeling of guilt. These incidents also get imprinted in their subconscious mind.
Now when a mind is so called idle, then whatever powerful impression is stored in the subconscious mind comes to the surface. If there are a lot of incidents associated with fear then they start running in the subconscious mind which one may consciously not be aware of. But this causes the person to experience feelings of anxiety and restlessness which may cause the person to take some destructive measures. But a slightly better way to deal with it is to divert the mind. One may do so by either watching television or talking to a friend or going for a walk etc. Doing such things may cause subconscious mind to run different incident from earlier life based on the new stimulus that he/she receives consciously and this may cause the person to feel better. But there is a problem with this approach. The feeling of fear is still hidden in the subconscious mind and it just needs another related stimulus or even idle state to come to surface again.
I personally look forward to days where I have an empty mind as it helps me in realizing what lies within me. When I start getting feeling of anxiety, I lie down and close my eyes and immediately an incident from my past which had feeling of fear associated with it, pops up. This process took time for me to master. Initially I feared where my mind would go (as I had many sexual thoughts) but as I let go that fear and let the mind go in all directions without inhibition, I was immediately provided with the incident which was the cause of my feeling of anxiety. I then stay with that feeling of fear, experiencing it fully. This is not easy as normal response of the mind is to run away. From my experience what I have observed is that when there is a strong desire to overcome the feeling of anxiety (because of certain compelling need) then one can stick with the feeling of fear and vent it out in various forms such as fast breathing etc. After the release of the emotional charge, I then could think about what belief caused the feeling of fear and with my current knowledge, I replace or internalize the new belief. After this I rerun the incident in mind and now there is no emotional charge associated with it and hence there is a feeling of ecstasy.
A person with a lot of tendencies not acceptable by his/her society will have a pile of incidents associated with fear. Ideally the person should clear off every major incident associated with fear but to see better result early on, one should start with older incidents and gradually come to recent ones. For a particular type of fear, one can follow the chain of incidents and try to reach the oldest one and then deal with it as it will have bigger impact. Now as explained earlier, during this process, we need to replace the older belief which requires an individual to do a lot of analysis about how the society works and not be a blind follower of some religious belief etc. Getting affirmation from emotionally stable people of your own character type may also help to internalize the new belief. A personal example would be to change the belief from masturbation is bad to masturbation is good. For accepting the new belief, I analyzed the functioning of the society, removed the sacred status given to marriage and got affirmation from responsible and happy people that it is good and then I was able to replace my older belief with this new one. But remember, I did it only after removing emotional charge resulting from feeling of fear and guilt while doing masturbation early in my childhood.
Meditation and Empty Mind
The process of meditation also takes a person towards an empty mind but in this process, instead of being evasive towards the feeling of anxiety (or so called disturbing thoughts), one should fight with it. This will cause the mind to eventually feel ecstatic as a result of overcoming the fear followed by actual stillness of mind.
Thus for most people, empty mind is actually a devil's workshop but for those who know and exercise the technique mentioned above, it becomes a boon. For people who do not have any subconscious fear (which I think are rare in today's complex world) an empty mind, without even application of any technique, is actually a step towards blissfulness and that's what meditation in earlier times by realized yogis, used to be.