The MT reads,
וּשְׁלֹשִׁים יוֹם וּשְׁלֹשֶׁת יָמִים תֵּשֵׁב בִּדְמֵי טָהֳרָה בְּכָל-קֹדֶשׁ לֹא-תִגָּע וְאֶל-הַמִּקְדָּשׁ לֹא תָבֹא עַד-מְלֹאת יְמֵי טָהֳרָהּ.
Then she shall continue for thirty-three days in the blood of her purifying. She shall not touch anything holy, nor come into the sanctuary, until the days of her purifying are completed. (ESV)
What is the meaning of this ambiguous phrase "blood of her purifying"? We know that vaginal blood contracts impurity upon the woman, so why would the bible call the impure blood here "blood of her purification"? Are we supposed to read this as "purification of her blood"? It is hard to see how impure blood would be considered in any way part of her purification process. The NJPS translates, "She shall remain in a state of blood purification", which I think agrees that the intended meaning is purification of the blood, not the other way around. I would appreciate some insight on this.
I'm asking because Jewish tradition has developed its own interpretation of this phrase which led to a principle called dam tohar. I was wondering, is the text cryptic enough, exegetically speaking, as to justify the Rabbinic hermeneutical methods and means taken to explain it (whether one agrees with it or not), or has the text been complicated needlessly?