There’s still some time left until Christmas, but Singer Peter Hollens has put together an early Christmas present to us all in his newest a cappella arrangement of “Mary Did You Know?”, and it’s absolutely beautiful. The amazing artist is so good that he’s able to sing a duet (I guess we can call it that) with himself. Yep, you read that right! In fact, he is a one man a cappella group. How is this possible? Well, the man sings all the parts of a song beforehand and then layers all the pieces together so that they blend in perfect harmony.