At http://popular-archaeology/com/issue/september-2011/article/royal-statua… (if link does not work go to http://popular-archaeology.com and scroll down for the article) … is a nice subject that illustrates the differences in culture in Egypt between the 3rd and 2nd millenniums BC. There are noticeable changing trends and fashion in statuary – and in the underlying religion and view of kingship. It was evolving. One major trend was the development of portraiture – and naturalism in art. In the Old Kingdom statues were thought to possess divine power, a repository of the king's spirit – ka. This was particularly relevant when the king was in his afterlife – had left the real world behind. Statuary therefore had a strong funerary association and was often hidden away – and taken out during ceremonies and anniversaries. Statues became the focus of cults of the dead king linking the living with the dead.
Now, it could be argued that this is a modern interpretation – but in the Middle Kingdom statuary was associated not with just the dead king but the king when he was alive. They were placed in temples.