Merry Golfmas, Everyone! It's Christmas everybody, and here's a code-golf challenge to celebrate. You need to make a program to print out a present. Specifically, the words "Merry Christmas". BUT, there is a catch: this program must only work if it is the 25th of December. If the code is run on any other day, then the program should crash.

This is Code-Golf, so the answer with the least amount of bytes wins.

Merry Christmas!
Pyke, 21 bytes
.dↄґ6C65h*325q/Al

Try it here!
     C65h*        -   multiply the day by the (current month + 1)
          325q    -  ^ == 325
    6         /   - 6 / ^
.dↄґ              -  load &quot;merry christmas&quot;
               Al - ^.capwords()

Or 18 bytes noncompetitive.
.dↄґ6Cs6Y1q/Al

Exactly the same except for this section:
Cs6Y1q 
C      -    get_time()
 s6    -   add 1 week
   Y   -  get day of the year
    1q - ^ == 1

Try it here!