There are three gunas as described by our scriptures. They are RAJAS, TAMASIC, and SATVIC. The man is govrned by these gunas. The characterstics of rajas are: violent, ruthless and always shows penchant for fighting.
The characterstics of tamasic are: indolent, too obsessive, always floats mean ideas in the mind.
The characterstics of satvic are: showing compassion, peace loving nature and more inclined towards spirituality
If one look at lord Shiva trident(trshul) it signifies that these three qualities. But, all three qualities are kept under control. An equilibrium has to be maintained otherwise it will be disastarous.
One can easily get rid of rajas and tamasic nature(for example, after the Kalinga war King Ashokha took to sanyas previously, he was obsessed with power, no compassion for others. But the war had transformed him into a monk.). Likewise, A sage called Aruna Giri Nadhar in Tamil Nadu before turning into an ascetic he was simply in the company of women this shows he was under the influence of tamasic guna.Once, he got rid of that guna he turned to spirituality.
The irony is it is impossible to get rid of satvic guna. This guna is called "intensified-intoxicants" which sometimes pull down the man's character. For example, if everybody becomes monk or ascetic who will govern the country and the administration . If everyone becomes vegetarian wilL there not be an imbalance in herbivorous animals. Being under the influence of satvic nature always provide a kind of "kick" which will pull you down.
In the end, one has to strike a balance among the three just like Lord Shiva does.
Each idol has its own interpretations. they are otherwise known as "bhava"(feelings)of the human beings.
