What is the copyright law concerning Hard copy to digital copies?

Hello, i've bought several hard copies of the NIV bible translation (which is copyrighted). I was wondering what the U.S Copyright law has to say about me getting the digital copy. I can pay for it ($40) but i would perfer not to considering I have copies of it already. I'd like some copyright citations to support your answers please or I won't have a definite answered question! Thank you guys and hope to get a answer!!