Brahman is without qualities. He does not have a form. But when the Brahman is associated with maya (Shiva and Shakthi in a single form called Arthanadeeswarar) he is called saguna Brahman, which means Brahman with qualities. The opposite of saguna is nrguna meaning without qualities. The qualities or gunas are attributed to the Brahman, because of the presence Shakthi or the kinetic energy. Shakthi is also known as maya. Maya is in the form of a veil and when the veil is removed the pure Brahman is there. Now we have two options to meditate upon. One is the Brahman with qualities or attributes. It is easier to meditate upon an object than meditating upon a sunya or vacuum. This is because of the ability of our mind to manifest on a form or qualities. There is nothing wrong on such meditations, at least in the initial stages of spirituality. But what are the qualities that can be meditated upon? For instance we can meditate upon his mercy, compassion, love, etc. The higher the qualities on which you meditate, more you identify with the Lord. Once you reach this stage of identifying yourself with the Lord, you get super human powers which are called siddhis. If you desire liberation, you have to proceed further from here. If your desire is for worldly life, you continue your activities with such powers and make a living. In the process you forget the ultimate destination of spirituality, merging with the Brahman. Please remember that identifying is different from merging.
When you accumulate more and more of your karmas by enjoying and enacting the supernatural powers gifted to you by the Lord, you become frustrated with such worldly pleasures and decide to move forward to the next stage. Unfortunately, you realized this in the final stages of your present birth. You do not have time to mend your ways. The life comes to an end and you are reborn to enjoy or suffer out of the sanchita karmas that you have accumulated over several births. Sanchita karma is the bundle of karmas that we have accumulated over our past births. Only a portion of this bundle which is called prarabdha karma is unfolded during this birth and rest is carried over as agamya karmas to give effect in the future births. Our birth stops only when this agamya karma becomes zero.
When you decide to advance in spirituality, please do not succumb to these siddhis. At the most you can test them for your own satisfaction. You could have observed that people with such powers always worship a particular form of God. These forms are mostly feminine which confirm that Shakthi is the kinetic energy. She is in the form of all the objects that exist in this universe. All these forms are perishable at some stage of their existence. In this case you have attained these siddhis by means of your meditative powers. But you do not acquire knowledge about the Brahman. Knowledge alone gives you the final liberation, not the meditation.
Meditation is nothing but a tool to work with. Since you have mastered the techniques of meditation, you have all the qualities to merge with the Brahman. This stage is called kaivalyam. This is the final stage. Since you have merged with Brahman, there is no second other than the Brahman. In the earlier stage there were two, one is the Brahman and another is you. Since ‘you’ have merged with the Brahman, there is no second. Our ultimate aim should be to reach the stage of kaivalyam.