What quotes from the crucible show that Danforth is prideful?

Justice Danforth exhibits his pride throughout the play. His attitude that his authority equals justice is one factor that both extends and increases the severity of the punishments for "witches" and those who defend them.
A simple question is quite telling. Even when someone asks him a basic question, he dismisses it as an affront: "you surely do not doubt my justice."
Constantly asserting his authority as absolute, he rejects any defense of the girls as impious questioning of "God's law."
The extent to which Danforth's pride threatens the whole community is shown when, despite knowing that some confessions and accusations were fabricated, he refuses to halt the proceedings.

Postponement now speaks a floundering on my part; reprieve or pardon must cast doubt upon the guilt of them that died till now.

Not only will it seem that the earlier executions may have been unjust, but he's worried that his reputation will be tarnished.