* When the Grail Knight says, "He chose... poorly", he's not referring to Donovan's selection of the Grail - he never picked the Grail, Elsa did. The Knight is stating Donovan's choice of ''allies'' was poor.
** [[TakeAThirdOption Or, you know, both]].
*** The line works either way. Donovan still believed the False Grail was the real thing. "This truly is the cup of the King of the Kings" and all.
*** However, Donovan still had no idea what the Grail would look like. He would have said that had Elsa picked the actual Grail.
*** He didn't choose a grail. He ''chose'' to let Elsa decide, and then he ''chose'' to listen to her. And he never ''chose'' to ask Indiana Jones, who up until that point had found a way past all the other traps and tricks that had killed everyone else before him. Above all else, he chose ''not'' to decide for himself - the worst choice of all.
**** He might have noticed that Indiana was obviously struggling to keep his mouth shut. Hero that he is, Indy was probably sorely tempted to tell him, "That's ''not'' the Grail."
* Henry Sr. talks Indy out of trying to get the Grail by calling him Indiana. Not only is he recognizing him as an equal, by calling him his preferred name, but Henry Sr. had spent his whole life looking for the Grail, and he's decided it's time to go on without it. And afterwards, when Indy asks him what he found at the Grail temple, he says "Me? Illumination.", which is a CallBack to the beginning, as when Henry [[NotNowKiddo ignored him while working on the Grail diary]], he said "May he who illuminated this, illuminate me...".
* When Donovan recruits Indy to look for the Holy Grail, he says "Find the man, and you will find the Grail.". He not only speaks of the Grail itself, but Indy's relationship with his father, with whom he's been estranged for years. It's this search for the Grail that brings them together.
** Steven Spielberg said it himself in behind-the-scenes interviews, "the search for the father is the search for the Grail".
* Indy hates his father because he was never there for him growing up, because he was working on his grail diary. But as an adult, despite his PapaWolf reputation from [[Film/IndianaJonesandTheTempleOfDoom the previous film]], [[NotSoDifferent Indy's never there for his children either!]] As a professor, he has dozens of students wanting to speak with him about his stacks of ungraded exams and papers and numerous phone messages, because he was focused on his own pursuits, such as the Cross of Coronado.
** Er, Indy had no idea he ''had'' any children.
*** I think the above troper means it in the sense that Indy is a professor and has a responsibility towards his students, who are like his children.
* The results to choosing poorly with the Holy Grail is a no brainer for Catholics & Orthodox. This is why they are so picky about Communion. They aren't being unwelcoming. They are trying to protect those who don't know the dangers. To wit:
-->''So then, whoever eats the bread or drinks the cup of the Lord in an unworthy manner will be guilty of sinning against the body and blood of the Lord. Everyone ought to examine themselves before they eat of the bread and drink from the cup. For those who eat and drink without discerning the body of Christ eat and drink judgment on themselves. That is why many among you are weak and sick, and a number of you have fallen asleep [in death].'' (1 Cor 11:23-34 NIV)
* Indy is implicitly or explicitly portrayed as a knight multiple times throughout the film, such as when he uses an improvised lance against a Nazi motorcycle-trooper, or when the grail-knight refers to him as such during the film's climatic scene. The scene with the tank takes on increased significance in light of this, as it portrays Indy as a lone hero on horseback fighting against a massive, unstoppable, firebreathing (in a manner of speaking) monster.
* Elsa Schneider knew that the grail she chose wasn't the right one. Even though Dr. Donovan was the BigBad, she still murdered someone in the presence of the Cup of Christ.
** Murdered, or executed?
** So she killed one Nazi. [[WhatMeasureIsAMook How many Nazis did Indy kill in this film?]]
** The Cup of Christ can't object all that strongly to killing people who try to claim it for the wrong reasons, considering it's guarded by deathtraps and an armed warrior.
*** See FridgeBrilliance above regarding "choosing".
* Given the location (the final resting place of the Holy Grail) and the reason for the pit's opening (greed/lust for power) it's entirely plausible that the pit Elsa fell into leads directly to Hell itself.
* The Leap of Faith trial. There's no way a narrow path could be successfully painted to perfectly blend in with the opposite side of the ravine it spans from ''both sides at once''. If it were just from Indiana's side - the only one that'd really matter for the trial - this wouldn't be an issue, but the camera cuts to the opposite side of the ravine and the path is just as invisible from that side as it is from Indy's.
** Then of course that doesn't take into account numerous other factors, such as wind, wear and tear, fading of the paint, wind, and most crucially, the time of day. Unless the cavern was lit artificially, then there's no way that the bridge would blend in with the cliff and it would be completely obvious. Now of course, if the bridge appeared ready to fall apart as you stepped on it, that would still mean a required leap of faith.