人在做，天在看 [rén zài zuò, tiān zài kàn]
People are doing [things]; God is watching. This Internet slang term is a caveat that doing bad things will bring bad karma.
In a foreign country [France] there is a kind of tent called “Bubble” enabling you to have a panoramic view. Lying down in such a camp and watching the starry sky must feel awesome.
People are doing things [fxxking], God is watching.
[Note: This punchline gives the original Internet slang term a twist. As an Internet slang term, 做 [zuò] means “to have sex”.]