To realize God, you need not worship statues. No one has said that only by worshipping a stone image of Shiva will you realize him. If you want to find God without any medium at all, you can certainly do so. All the saints have said this. They have described two paths to reach God: vihangam marga, the path of the bird, and pipilika marga, the path of the ant. If you are a bird, you may fly straight from where you are. You do not need a bus or car. If you have wings, fly like a bird and you will certainly reach that supreme spirit and realize him. But those who do not have wings can use the method of the ant. The ant has to traverse the whole distance.
The path of the ant is for those who are caught up in the attachments and illusions of the world, who are under the sway of their mind, the gunas, likes and dislikes, who feel happy with one thing and sad with another. Such people need some kind of a base to realize God. This base is the mind.
With the mind as the base, you internalize, go within. The supreme spirit that you wish to realize may exist externally, pervade the whole world and creation, but it exists within you too, so the mind is used as the base to realize it. But you must properly understand what kind of base the mind is.
Say, you pick a rose from a garden. The rose is separate from you. You see it as an object and it is separate from you. When you close your eyes and try to visualize the rose, you see the rose within. This rose is different from the rose you plucked from the garden. Mark my words: the rose that you have placed on your desk and the rose that you are looking at within your mind are different. One is para, external, and the other is internal. What you see within is not a rose blossom, but with the image of the rose blossom as the base, you are seeing yourself. When you worship the images of Rama, Shiva or Devi in a temple, when you close your eyes and meditate on them, what you see within at that point is not them, but you. You are the image of the supreme spirit, you are its resplendence. Assume that you close your eyes and see me. The image of me that you see by closing your eyes is not me, but you. Until you grasp this matter, you will not find the answer to your questions.
The supreme spirit makes itself attainable. The base and the external guru are left outside; the guru who shines within is your own self. The statue of Shiva that you look at is you. He is not the Shiva residing at Baidyanathdham or Vishwanath temple. That which is within is real. What is realization of mind, consciousness and self? People focus their mental energy on the image of a rose or shivalingam. Slowly, they stabilize their mind on a symbol. After some days, that experience is lost, it goes away, nothing and no one remains. In that nothingness, the image of God exists and does not exist at the same time.
How can I tell you whether God has an image or not? No one has been able say this. No one has had the last word on God. They have not been able to say that God is not stone. Has anyone said that? If someone says that God is not an image, what proof do they have? What is the proof that God has a form or is formless? No one has ever been able to prove either. A Muslim cannot give proof of Allah, a Christian cannot give proof of God and I cannot give proof of the soul. God is beyond proof, he is unprovable, immeasurable.