on pain of their lives to suffer nobody to pass out?

I faced difficulty understanding the sentence below;

(He) charged his domestics on pain of their lives to suffer nobody to pass out.

I found that the phrase "charge someone on pain of" means that they are subject to punishment. So I suppose it means they are subject to capital punishment (their lives), but I can't understand what's given next (to suffer nobody to pass out).

Presuming on the unshaken submission of Hippolita, he flattered himself that she would not only acquiesce with patience to a divorce, but would obey, if it was his pleasure, in endeavouring to persuade Isabella to give him her hand — but ere he could indulge his horrid hope, he reflected that Isabella was not to be found. Coming to himself, he gave orders that every avenue to the castle should be strictly guarded, and charged his domestics on pain of their lives to suffer nobody to pass out.

The young peasant, to whom he spoke favourably, he ordered to remain in a small chamber on the stairs, in which there was a pallet-bed, and the key of which he took away himself, telling the youth he would talk with him in the morning. Then dismissing his attendants, and bestowing a sullen kind of half-nod on Hippolita, he retired to his own chamber.

Solution 1:

To charge someone = to give someone an order that they have to obey and execute.

On pain of xyz = if they fail, they will be punished in way xyz. On pain of their lives means indeed that if they fail, they will be killed.

To suffer = to allow something (to happen). This is archaic, or at least old-fashioned. It is still used occasionally in this sense, and in fixed expressions like not to suffer fools gladly. Maybe the best-known use of it comes from the King James Bible:

Thou shalt not suffer a witch to live.

Which in the New International Version has been rendered as:

Do not allow a sorceress to live.

source

Pass out in this case should be read literally. Pass means move by, pass out means move to the outside. In short: leave.

So a modern version of the sentence would be:

He told his servants that nobody was allowed to leave the castle. If anyone leaves, the responsible servant shall die.

What makes this sentence especially interesting is the collection of words and expressions that (nowadays) have a different common meaning:

Charge with = accuse someone of a crime
Suffer = to undergo something, to experience pain
Pass out = to faint

So it is fully understandable that a first reading of the sentence would lead to something like "He accused his servants because none of them had fainted — for that they will die." — which makes little to no sense in the story (or otherwise) of course.