Reply To: V'nishmartem Meod L'nafshoseichem

Also, the Perisha in his hakdama writes that the Levush when explaining the reasoning behind halachos, did not get them from the Gemara. Instead he used the Beit Yosef and when the Beit Yosef didn’t give the reason, the Levush made up the reason. In this case,the Beit Yosef does not discuss the source that Chazal used to assur dangerous things, so perhaps the Levush was just saying this on his own.