Praying using an icon or a statue is exactly the same as using Skype to talk to God. It is a way of communicating with God.
Statues or icons are like telephones. When you want to call someone, you can pick up your telephone and dial their number. Then you can communicate with them. The telephone is simply a tool that you can use to reach them. Praying using an icon or an image of a God is exactly the same thing.
When Hindus pray using an image of the deity, they don’t believe that the deity is that image. They aren’t worshipping the image. They are worshipping what is inside that image. The image is a way of receiving the divinity. They believe that when they pray, God sets up residence inside that statue during that time, and that they can see and be seen by God. When the prayers are over, God departs from the statue.
Icons, used in Catholic and Orthodox traditions, are simply “windows” to the divine. The divine isn’t there, but it can be used as an interface. It is an access point.
Now, God is always present. God can be accessed anytime, anyplace, and anywhere, by anyone. But we humans can’t really handle that. That is a little too much for us. So we can set aside time to be with God. This makes it more manageable for us, and more likely we will listen to the message.
God can speak to us through dreams or burning bushes like was done with people in the past, or in any number of other ways. God is constantly trying to get our attention. The problem is that we aren’t always ready to receive. We may brush it off as coincidence, or an accident, or just simply not meaningful. We aren’t ready to receive the message when it comes.
Using an icon or an image of an aspect of God puts it on our terms and on our time. We choose the time we approach, and how we would like to interact with God. This makes the infinite more human-sized. We can then enter into the mental space ready to receive whatever message we are given.