Why is the Virgin Mary is like an Old Testament Assassin?

Judges 4, which recounts the story of the fall of Israel after the death of the judge Ehud, provides some interesting parallels with Luke 2.

In Judges 3, Ehud assassinates Eglon, the king of Moab. Following in Judges 4, we have another assassination story, in which Jael kills the captain of Jabin's army.

Judges 4 is one of those accounts in which Israel is in terrible shape, and conditions are very bad. The prophetess Deborah is judging the nation at that time, and Barak is the chief of her armies. He is nevertheless fearful, and will not go up to the battle without Deborah's presence. She in turn warns him (vs. 9): "I will surely go with thee: notwithstanding the journey that thou takest shall not be for thine honour; for the LORD shall sell Sisera into the hand of a woman."

Barak apparently thinks that the woman in question is Deborah. It is not.

In one of those interesting twists, we read that "the LORD discomfited Sisera, and all his chariots, and all his host, with the edge of the sword before Barak; so that Sisera lighted down off his chariot, and fled away on his feet." (vs. 15) After fleeing on foot, he comes to the tent of Jael. She in turn invites him in, encouraging him to "fear not." (vs. 18)

One of the implications of the text seems to be that Jael was acting as though she was a prostitute. I can't say that for sure, but several reasons make me think this. First, vs. 9's statement that Sisera would be "sold" into the hands of a woman. Secondly, Jael's hospitality is unusual, because as a woman alone, it seems unlikely that she would have invited this general into her tent without her husband present. Third, Sisera seems to have no compunction about entering her tent; an unlikely event without the subterfuge of her playing a prostitute.

(Prostitution is an old subterfuge in warfare and espionage. A large example, of course, is that of Rahab, who hid the Israelite spies. A whorehouse is a spot where strange men entering would not be thought unusual, and that's very likely the reason why the spies stayed there. A prissiness that wants to make Rahab an "inn-keeper" is avoiding the point of the text).

Jael, however, goes from being a prostitute to being a mother: when Sisera requests water, she instead brings "milk," very possibly a buttermilk-like substance, but still an obvious way of calling attention to herself as a mother. She continues a nurturing behavior by covering Sisera (vs. 18) and protecting him (vs. 20).

But after he's asleep, she performs the act prophesied by Deborah: she takes a tent-peg, and hammers it through his head. Judges 5.26 seems to further indicate that she may have decapitated Sisera as well.

What is interesting about this courageous woman is the words used to describe her by Deborah in Judges 5.24: "Blessed above women shall Jael the wife of Heber the Kenite be, blessed shall she be above women in the tent."

A very similar wording is used in describing the Virgin Mary in Luke 1. The angel Gabriel spoke to her (vs. 28): "Hail, thou that art highly favoured, the Lord is with thee: blessed art thou among women."

Later in the same chapter, Elisabeth "was filled with the Holy Ghost: And she spake out with a loud voice, and said, Blessed art thou among women, and blessed is the fruit of thy womb. " (vss. 41b and 42)