Jews should not defend themselves

 The following was written in the aftermath of the Chmelnicki massacres, He says the rabbinic leaders felt that resisting the attacks would ultimately lead to  a greater number of Jews being killed.

The author is ר גבריאל בן יהושע שוסברג there are תשובות in halacha from him. He says that that was the  פסק הוראת הגאונים הרבנים that was followed by the people then as a "הוראת שעה" it's not clear if that means כפשוטו that it's not standard halacha or that the circumstances then required it.