"I am so ashamed of the double life that I have been living and am grieved for the hurt, pain and disgrace my sin has caused my wife and family, and most of all Jesus and all those who profess faith in Him."
It was reported that Duggar, whose show 19 Kids and Counting has made him the darling of US conservatives, allegedly had multiple accounts on the cheating website - revealed in a huge hack of the site by a secretive group called the Impact Team.
It is just the latest controversy for the star after he was forced to admit molesting four of his nine sisters as a teen.
Those revelations brought an end to his family's reality TV dream.
In the latest statement, Duggar implies he hadn't previously admitted being unfaithful or his online pornography antics to his family or wife.
He doesn't explicitly admit to using Ashley Madison but the timing certainly adds weight to the allegations.
EXPOSED: Government staff details on hacked cheating website
"I brought hurt and a reproach to my family, close friends and the fans of our show with my actions that happened when I was 14-15 years old, and now I have re-broken their trust," he continues.
"The last few years, while publicly stating I was fighting against immorality in our country, I was hiding my own personal failings.
"As I am learning the hard way, we have the freedom to choose to our actions, but we do not get to choose our consequences. I deeply regret all hurt I have caused so many by being such a bad example.
"I humbly ask for your forgiveness. Please pray for my precious wife Anna and our family during this time."
The Ashley Madison account allegedly listed to Duggar's full name and address said that he was looking for "conventional sex, experimenting with sex toys, one-night stands, sharing fantasies, sex talk," and more.
Outrage at radio stunt
Radio listeners aren't happy that a Sydney woman was told live on air that her husband is registered with Ashley Madison - a website for casual affairs.
Nova radio hosts Fitzy and Wippa offered to find out if the suspected person was registered with Ashley Madison by checking their email address against the data released by hackers this week.
Jo (name changed) from Blacktown took them up on the offer. "We're putting him into this website right now and his details have revealed that he's actually on the website, Jo," said Fitzy.
"Are you freaking kidding me?" Jo asked. "Yeah, no ..." stammered Fitzy.
Listeners have taken to Twitter to voice their outrage. "I for one do not want to listen to you two destroy someone's life on air. It's not funny. It's horrible," tweeted The Sydney Rant. Alexander Rose-Innes tweeted: "You guys are a shameless disgrace."
After Jo hung up, Wippa said: "Oh I don't know if we should have done that. That hasn't left me with a good feeling." Fitzy said: "I'm sorry that that happened, Jo. I feel a bit bad."
- Daily Mail, AAP
