Josh Duggar is not only facing tough criticism in the press after it was revealed he had a profile on adultery website Ashley Madison, but those within his tight-knit Christian community are calling out his hypocritical behavior as well.

In a blog post published Monday, Josh's in-law Michael Seewald said the 27 year old's secret extramarital sex life is an example of taking the lord's name in vain.

Michael Seewald is the father of Ben Seewald, who married Josh's younger sister Jessa, 22, in a two-hour televised special last November.

While Seewald says he stood behind Josh after it was revealed that he molested four of his younger sisters when he was a teenager - including Seewald's daughter-in-law Jessa - he says the adultery revelation was the final straw.

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Criticism: Michael Seewald, pictured right, whose son Ben is married to Josh Duggar's younger sister Jessa, weighed in on the Ashley Madison scandal on Monday. Josh pictured on the left with his wife Anna

In his blog post, Seewald draws on several anecdotes from the Bible, preaching against adultery.

He says that while Christians do sin, Josh's actions were so much worse because he pretended to be of upstanding moral fiber.

He flourished in the fame of his family and the success of their television show, all the while betraying their trust and Christian values Michael Seewald, father-in-law of Jessa Duggar

'He claimed to be a Christian, but by his deeds he has suggested otherwise. With the name of God on his lips he lived a covert and extensive lifestyle of evil.

'While proudly saying things like, “Our family is like the epitome of conservative values”, he was looking at porn and soliciting affairs.

'He took a job at the Family Research Council that exists to promote the traditional family, all the while undermining his own family by violating his marriage covenant.

'He flourished in the fame of his family and the success of their television show, all the while betraying their trust and Christian values.

'The thing that is so hurtful is that he was a loud voice endorsing Christian ethics and he has been shown to be a fraud. I am profoundly grieved that he attained such a platform only to bring shame on God’s holy name and the Christian faith,' Seewald wrote.

Husband and wife: Ben Seewald married Jessa Duggar in a two-hour televised event last November

Seewald says he felt compelled to weigh in on Josh's scandal because of the way his actions have tarnished their close-knit Christian community to the rest of the world.

And while he never got to know Josh well, Seewald says he feels for his family who are now suffering because of his choices.

'In commenting on this I do not wish to add any more distress to a family still recovering from the indignity of the publication of a police report detailing Josh’s sins as a teenager...

'I have great respect for his sorrowing parents and immense sympathy for his dear wife, Anna, and their four children,' Seewald wrote.

Seewald's blog post was published just one day after sisters Jessa and Jill Duggar, along with their mother Michelle, appeared in a TLC documentary special on sexual abuse of children.

'I feel like this should be a discussion people are having, even regularly,' Jessa opened up on the special.

'I think that it shouldn't be a taboo subject, that we should be bringing awareness to child sexual abuse and talking about this.'

Over the weekend, Jessa also appeared at the Southern Women's Show in Charlotte, North Carolina where she promoted her new book Growing Up Duggar: It's All About Relationships.

Asked by People magazine how she is coping with all the adverse publicity surrounding her brother's confessions of adultery and porn addiction, she replied: 'You just have to keep your focus and trust God.'

Jessa, who is seven and a half months pregnant with her first child, was accompanied at the event by her husband.

It was revealed in May that Jessa and her older sister Jill were among five girls molested by Josh Duggar when he was a teen. The news led to the cancellation of 19 Kids And Counting by the TLC network.

The sisters went on Fox News in June to talk about what had happened and Jessa defended her brother and said she had forgiven him.