Practitioners of Non-Duality or Advaita will tell you that it is the only true state of existence and awareness is only possible through the dedicated practice of Advaita. It is also said that pure consciousness can only be experienced through Advaita and it is the only method of knowing God.
This is the real truth, however, there is also a very credible school of thought, which says that existence cannot be complete without Dvaita or Duality. This school of thought says that life is not possible without the inter-play of the positive and negative, some Hindu philosophers say that the mind and thoughts, which make up the personality or ego of an individual is nothing but the sum total of all the experiences, the individual experiences ever since the fetus gains consciousness in the womb.
A person who see everything scientifically should ponder upon the nature of the three components of an atom, proton=positive, electron=negative and neutron=no charge. The protons and electrons [negative and positive]are perpetually attracted to each other.
In my opinion, and I have said it many times earlier the ego is the sum total and interplay of the three Gunas- the Satvik, Rajasik and Tamsik Gunas. This for the advanced Sadhak corresponds to the Hindu Divine Trinity of Brahma, Vishnu and Shiva.
Does this mean that the most powerful form of prayer should transcend even the Divine Trinity? Yes, for the advanced spiritualists, Sadhaks and Yogis, to experience God or pure consciousness, the Divine Trinity should also be transcended and the only thought form should be that of total Silence.
To an extent sheer Bhakti is also capable of throwing out the chain reaction of never ending thoughts and stilling the mind on the Ever-Existent, the Ever-Existent for the Bhakt can also apart from silence mean his preferred deity like Ganesha, Shiva, Vishnu, Hanuman or any other deity.
The material and psychological wants of an individual can also be met through silent prayer. The greatest of all the practitioners of Non-Dualism, Adi Shankara popularized a form of worship know as Manas Puja or Mental Worship especially for those in the lesser advanced stages of spirituality wishing to evolve. This form of worship is meant to aid the spiritual progress of the Sadhak and eventually lead him towards silence. An example can be seen here – Shiv Manas Puja