Joshua 2:16-20

Verse 16

Hide yourselves there three days - They were to travel by night, and hide themselves in the day-time; otherwise they might have been discovered by the pursuers who were in search of them.
Verse 18

This line of scarlet thread - תקות חוט השני tikvath chut hashshani. Probably this may mean, this piece of scarlet cloth, or, this cloth (made) of scarlet thread. When the Israelites took the city this piece of red cloth seems to have been hung out of the window by way of flag; and this was the sign on which she and the spies had agreed.
Verse 20

If thou utter this our business - It was prudent to make her life depend on her secresy; had it been otherwise she might have been tempted to give information, not only concerning the spies, but concerning the designs of the Israelites. But her life being at stake, added to every other motive, she kept the secret for the sake of her own personal safety and that of all her relatives.
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