When you google phrases to assess their frequency, it's worth going to the last page of returns, to see what Google says.
With "keep the silence", for instance, you'll find something like:
"Results 751 - 751 of about 706,000 for "keep the silence". "
Followed by: "In order to show you the most relevant results, we have omitted some entries very similar to the 751 already displayed."
In other words, Google has decided that the other several hundred thousand hits are duplicates, cached versions, or quotes of one another.
To answer your question, I would say that all of those variants might be used; though #5 has a poetic or Biblical air, and few opportunities would arise for #6 or #10.
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