It is permissible for a strange man to seclude himself with two women [who he is not mahram for], but not the opposite, meaning that it is impermissible for two strange men to seclude themselves with a woman, even if the likelihood of them colluding to perform indecency is low, as Nawawi articulated in his book, al-Majmu`; because a woman’s shyness in front of another woman is more than a man’s shyness in front of another man. However, in his explanation of Sahih Muslim, he (Nawawi) interpreted the statement of the Prophet (peace be upon him), “After this day no man should enter upon a woman in her husband’s absence, but only when he is accompanied by one or two other men,” to imply to a group of men whom the likelihood of colluding to perform indecency is low due to righteousness, manhood, or other such qualities.
[Asna al-Matalib, Shaykh Zakariyyah al-Ansari al-Shafi`i (3/406)]
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