That though it is you I shall marry.
I have been chosen to bear the Messiah
And it will be God's child I carry"
Now this is a blast from my past, something that I remember doing at my Playgroup before I started school, but you can not get Borax now, so need to use Borax substitute (I got mine from the chemist).
Then mix your borax solution with boiling water and add blue food colouring. I used about 6 tablespoons to approximately one pint, but I just poured it in (I am not an exact type of person).