In the wake of the March 15 mosque attacks in Christchurch, the Government proposed to include hate speech in the Crimes Act, removing it from the Humans Rights Act.
The reform would introduce maximum penalties of three years in prison and fines of $50,000.
Seymour said this would impose on freedom of speech, which was covered in the Bills of Rights Act.
His three-week nationwide tour came to an end this week, when he spoke to about 280 people at the McFaddens Centre in St Albans Baptist Church.
"Free speech cannot survive any oppressive regime," Seymour said.
He said people were "walking on eggshells" these days and believed the law reform would make that worse by placing more restrictions on free speech.
Seymour wanted people to separate the argument from the person. The government ought to focus on the 99 percent that united us, not the 1 percent that separated us, he said.
"People are enormously concerned about what restrictions on speech might do. They feel it is already difficult to express their views and a government legislating against what they might do."