You may not be able to recognize the words, but the melodies of traditional Christmas carols are often unforgettable whether sung in your own language or in another.
Here is a real Christmas carol classic, Hark the Herald Angels sing sung, very well, by a choir of Italian children.
In Italian, Hark the Herald Angels sing is Ascoltate! Gli angeli messaggeri cantano.
Even if the words were not too familiar, I’m sure you recognised the melody.