B is for Bethlehem - Isabel Wilner
An alphabet book of the highest caliber - very strong vocabulary, complex folk art drawings - a beautiful book. We have it in board book, but my kids probably won't understand and enjoy it until they're older than board book age.
Christmas in the Manger - Nola Buck
It tells the sacred story in simple rhyme. Even after reading it 10 times in one day, you won't be going crazy. My favorite page "I am Mary, the mother mild, how I love my tiny child." Bonus - my son loves the sparkly star in this book.