Commentary for Joshua 5:2

Sharp knives. As translated by Targum, sharp knives. Similarly, ‘You also turned back the sharp edge of his sword.’¹Tehillim 89:44. When the sharp edge is turned sideways it does not cut well. ‘Similarly, ‘Every weapon that is sharpened against you?’²Yeshayahu 54.

The second time. For there had already been a circumcision— on the night of their departure from Egypt a large assembly were collectively circumcised, and this was the second time; because during the entire forty years that they were in the wilderness the north wind did not blow for them, and they did not have a suitable day to circumcise themselves, as we learned in Maseches Yevamos.³Yevomos 71b. Certain atmospheric conditions were beneficial for the healing of the wound caused by circumcision. The north wind created this condition. These winds were withheld during the forty years in the wilderners in order that the “Clouds of Glory” that led and protected the people would not disperse. Our Sages said, “The second time refers to exposing the corona at circumcision. [This particular aspect of circumcision] was not commanded to our Patriarch, Avrohom.