Anyone who is a fan of Tom Lehrer, with his extremely pointed wit and knack for hilarious songs (although some you have to look out for), will know what this is a parody of, and therefore what tune belongs to it. Anyone who isn't has to look him up.
That's the trad-cat's marching song,
As through life you march along;
Be prepared to fight to prove the Faith is true,
Don't forget to pray and give Our Lord His due;
And behave extremely well,
To be sure
That you won't end up in hell,
If a devil comes to tempt you on a jolly summer day
Sign the Cross and say "Begone!" and he will scream and run away,
And you'll laugh to just remember how he stared...
That's the trad-cat's solemn creed,
And be clean in word and deed,
Go to Mass and say your Rosary each day,
So after death you'll have no stops along the way!
To be called for any time,
Keep your soul all free of grime,
So that when the Master calls you on the final Judgment Day
You can dash right up to meet Him with a smile bright and gay, --
Won't be nervous, won't be flustered, won't be scared --