Jennings, the 16-year-old star of TLC Network's "I Am Jazz" tweeted, "Every day I experience cyber-bullying, but I keep sharing my story. Today was no different."
"I Am Jazz" began in 2015 and follows the 16-year-old's life as a transgender female, which she "has been living as ... since kindergarten," the show's official website explains.
"Parents Jeanette and Greg have spent the years finding doctors to treat their daughter, while fighting the discrimination and misconceptions associated with what it means to be transgender," the description adds.
TLC tweeted out promotional material for "I Am Jazz," to which Dillard responded, "What an oxymoron... a "reality" show which follows a non-reality. "Transgender" is a myth. Gender is not fluid; it's ordained by God."
The responses on Twitter to Dillard included some calls for the network to take action against the 28-year-old.
TLC told ABC News in a statement that "Derick Dillard’s personal statement does not represent the views of TLC."
Dillard later tweeted, "I have nothing against him. I only have issue with the words and definitions being propagated here." Commenters were quick to correct Dillard and tell him to refer to Jazz as "her," not "him."
Dillard was back at it again on Friday, but it's not clear if his new comments are related to any backlash he's received from "I Am Jazz" fans and the transgender community.
"People are not my enemy; I fight against the cosmic powers over this present darkness, the spiritual forces of evil in the heavenly places," he tweeted, adding "Everyday, I seek to be less like the natural spiritual state I was born with and more like my lord whom I confess, Jesus Christ."