Rashi: It means 'Don't go to bed whilst his security (security) is still with you'.
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Why does the Torah insert the (otherwise superfluous) word "ve'Im Ish Ani hu"?
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Ramban (citing the Sifri): To teach us that the same Din applies to the Mashkon of an Ashir
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- and the Torah only writes "Ani" to teach us that Hashem will answer the cries of an Ani before those of an Ashir.
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