Denethor's dislike of Gandalf

[Boromir88]

Thank you for that wonderful post Squatter.

There has been always something else about Denethor too, which I think is a reason for Denethor's dislike on Gandalf. Eomer was on the right track, now just needs a bit of explaining.

Thus pride increased in Denethor together with despair, until he saw in all the deeds of that time only a single combat between the Lord of the White Tower and the Lord of the Barad-dur, and mistrusted all others who resisted Sauron, unless they served himself alone.
~Appendix A: The Stewards.

It's clear that Denethor doesn't trust those who don't fight under him. Whether you were with Sauron, or against him (like Gandalf) if you didn't fight under him, he didn't like you. This to me is a big contribution to why Denethor doesn't like Gandalf. As Eomer puts it, Gandalf sort of butts into everyone affairs. The problem is, that Gandalf has that power, as discussed here. Denethor takes Gandalf's authority the wrong way. He see's Gandalf as trying to butt in on his rule, and that's something Denethor doesn't like anyone doing. Denethor sees himself as supreme ruler over Gondor, and it's no one else's but his.

I would also like to mention Theoden in this situation. Tolkien establishes many connections between Theoden and Denethor. I wonder if he's trying to show us the difference between a King and a Steward? Or just show the differences between the two? The key figure in both (in their downfall and their rise) is Gandalf.

Both Denethor and Theoden lost their wife a while back. They lost their son in heir. They are watching their kingdom on the verge of destruction. They are both put under the power of their respected enemies. Theoden is under Saruman's control (thanks to Grima) and Denethor loses in his fight with Sauron totally losing his mind. However where they are different is Theoden is able to rise above all his hardships and win glory, and die in glory. In LOTR we see his low point, and he rises up to his high point. Denethor we see his slow decline until he loses his mind and burns himself. I think the main reason for Theoden's rise, and Denethor's downfall is...Gandalf.

Theoden although he is a king, he shows humility and accepts Gandalf's advice. He listens to Gandalf, on his way to Helm's Deep he even admits that now he's learned of Saruman's power Gandalf's words don't sound as good as they did in the Golden Hall, and he wishes he knew now what he knew then. However, Theoden still goes along with Gandalf's advice, intrusting his whole Kingdom into Gandalf.

Denethor on the opposite hand doesn't take anything that Gandalf advises. They are constantly butting heads. Denethor sees himself as ruler of Gondor, and doesn't care for anyone, or anything else.