Popular a capella group Pentatonix (PTX) has a Christmas album out and their new video of the popular Christian song "Mary, Did You Know" is taking the internet by storm with over six million view in just days.

The Texas natives released a Christmas album titled That's Christmas to Me on RCA records in October. The five-part group put out 11 songs in total and three of them are Christian songs about the birth of Jesus. Upon the release of the video of "Mary Did You Know" the group has now exposed millions to the story of the birth and life of Jesus by a conversation with his mother Mary.

Christian artist Mark Lowry wrote "Mary, Did You Know" and he had nothing but praise for the group. "Wow! These people are good," he wrote on his Facebook page after sharing the video with his followers. The song has been covered by a dozen other popular artists through the years including Kenny Rogers, Cee-lo Green, Rascal Flatts, Michael English and many others. None however have made such an impact in such a short time.

People on YouTube have nothing but praise for the a capella group. "Thank you PTX for being musically and personally courageous in performing this song - my respect for you has been high, and now has risen exponentially higher," one wrote.

"Thank you for being an uplifting and positive voice. You're appreciated," another added.

Watch the viral video of PTX's version of "Mary, Did you Know" below, and get a copy of their new Christmas album, That's Christmas to Me on iTunes HERE