The Duggars Wear Unusual Outfits While Snorkeling on '19 Kids and Counting' [Video]

Even when they go snorkeling, the Duggars preserve their modesty.

The stars of TLC's "19 Kids and Counting" are famous not only for having so many children but also for their strict religious beliefs. That's why they went swimming fully clothed while snorkeling during a trip to Puerto Rico in Tuesday night's episode.

As Michelle explained to People magazine, "Bathing suits are pretty and colorful, but it's not our thinking that it is OK to be naked some places and not other places."

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"The eyes are the windows to the soul. And we are trying to keep our hearts pure, which is a struggle," she continued.

"Everyone has their idea of what is modest, but for our family, we try to avoid situations ... like the public beach or swimming pools that can make it a challenge to keep our minds pure."

This isn't the first time they've swum in Wholesome Wear swimsuits, though the family generally avoids swimming in public. And the Duggars make sure to stay covered up for whatever activity they're doing -- whether it's swimming, riding horses, or climbing. Their modest dress code has the family's boys wearing long shorts and the girls wearing long skirts.

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"This isn't for everyone, and we don't push this on anybody," Michelle explained in TLC's Parentables blog. "And we don't judge anyone that doesn't have this perspective, but for us, we felt like we needed to be covered from our neck to below our knees."

"19 Kids and Counting" airs Tuesdays at 9 PM on TLC.