Yeah, that's almost as much a crock of shit as the classic "you must always, without question, respect your elders."
Yeah. At least mis madre gives some headway in the thought that "If a girl is coming at me with a knife, I must simply push them out of the way and seek help."
If I may, in some circumstances that JUST ISN'T POSSIBLE. Of course, being the personal shut-in I am, I've never been in such situations, but I know easily that they exist.
I feel lucky that I won't let myself be so vulnerable to such an irrational physical restriction that exists just because "That's the way it is". Of course, people may find that ethically refutable, but I don't really socially associate myself with such people beyond the internet anyway.
There is actually another side to this matter. Besides the obvious implication of "You should not hit women, they are the weaker sex and men bearing violence against them reveals him to be an unchivalrous brute and bully", there is a legal complication as well that necessitates heeding.
I'm not sure how many times you've been in a situation like this, but I've watched my Mother beat the shit out of her boyfriends without provocation. They are bloodied and battered and beaten, and they fight back too, but they leave few marks on my Mom in comparison to the abuse they receive. When the police arrive, they quickly haul the boyfriend away, and they console my Mother and ask if she wants to press charges against him, and she says no cause she loves him, and all the rest of the spiel.
Those are just my experiences, I don't want to sound sexist.