Holy Grail can't exist

I thought Jesus made the grail and seeing as some believe he is God personified, then yes Holy Grail would seem apt.
Or maybe I'm confusing what Indiana Jones says!

You goof! This movie is satire based on a famous English legend.

If you look into it, the myth of the "Holy Grail" is just that; a myth. Its sole purpose is to distract from what was important, the death and resurrection of Jesus Christ. In fact, Europe is littered with all sorts of artifacts that are medieval fakes and frauds, claiming that they have divine power, such as the head from the Spear of Destiny, or the Shroud of Turin. Nearly all of them date back to the medieval period in which they were first said to appear, rather than much earlier during the actual time of Christ.

As far as anyone knows, there are no artifacts out there imbued with divine power of any kind. They're just pretty objects that had a lot of hype put around them to get attention at different holy sites and to draw in pilgrims and visitors. It's not that different from the Smithsonian drawing in visitors with genuine artifacts from specific places and time periods, rather than having nice replicas made.

"Holy" and "sacred" are synonyms. No one claims that the Bible was created by God (each book in the Bible has named human authors), yet it is called the holy Bible - not the sacred Bible. Except, of course, in Latin, where it is called "Biblia sacra"

Besides, "holy" originates from Old English (ultimately Norse) and "sacred" from Old French (ultimately Latin), both instances of words meaning the exact same thing. Indeed, the fact that the Bible is called the Holy Bible and not the Sacred Bible - even though the Latin clearly uses the root word for sacred - is testament to the fact that these two words are completely interchangeable for most purposes. The only thing that determines which word is more appropriate, is tradition. Most other languages have only the one word for both "holy" and "sacred", after all, and the fact that English has two words is not important. It is simply the result of multiple influences.