What was the Hagia Sophia and what did it show about the Byzantine Empire and its power?

Hagia Sophia is Greek name, and it translates as "shrine of wisdom". It was a huge church of Christianity located in Constantinople, the capital of Eastern Roman Empire/Byzantine. Since building church of that scale cost an astronomical amount of wealth, it demonstrates the financial and political power (the ability to gather the necessary resource to build it) of the Byzantine when it built it.