Why do Hindus pray to stones and statues, pictures and posters?
Be it for any religion, when we pray to God our minds automatically begin to imagine a form or a symbol representing Him. It could be in any form; a man in a flowing robe of white, looking over from the heavens above, or just two eyes watching over you - to each his own or just as his religion has encouraged him to adhere to. A praying human will definitely imagine someone or something in his mind or even the simple letters of GOD in big image.
To the Hindus, and come to think of it, to most. God is everywhere, invisible to the human eye; He is all too powerful. He could be at the pillar behind you or the tree under which you are seeking shelter, all the time watching.
But the Hindus also believe that you could see God if really focus and feel for Him. They know the form of God is quite similar to man in essence. They carve out the silhouettes and profiles of God and Goddesses as relatively as told in the ancient chronicles and manuscripts on Hinduism. The carved sculptures are placed in the houses of the Gods and after holistic cleaning and prayers-accompanied purification they are ready to be worshiped as representations of the Gods and Goddesses. The statues of a God may portray to have many hands or the face made to look fierce but this is just to show the extreme power of the Gods and Goddesses. So now all a Hindu needs is to focus on the sculptural symbol of God and pray for his well being. To him the statue already has the soul of God in it. To the Hindus their prayers will reach God through any means if they truly and passionately pray to him. And that is why they also pray to the symbols of God such as the stone-carved phallus symbol of Lord (god) Shiva, the creator.
Pictures and posters are essentially the photo copies or the intricate and vigilantly laboured drawings of the statues of the Gods and Goddesses in their splendor. The houses of the Hindus will conveniently have these in their prayer rooms for them to pray at various occasions.