In Vayikra 14:19, there are different versions of the trop, and unlike most of them, this difference causes a change in the meaning of the words:
וְכִפֶּ֕ר עַל־הַמִּטַּהֵ֖ר מִטֻּמְאָת֑וֹ
(zakef-gadol, tipcha, etnachta)
and he will bring atonement for (the one becoming pure from his impurity)
(This is the one I've seen in most places, including Artscroll and Mechon Mamre; Simanim ascribes it to the Keter and תאג' תורה קדומה [I have no idea what that is])
וְכִפֶּ֥ר עַל־הַמִּטַּהֵ֖ר מִטֻּמְאָת֑וֹ
(mercha, tipcha, etnachta)
(and he will bring atonement for the one becoming pure) from his impurity
(Simanim gives this as the default, and Koren uses this one)
It's possible that this has halachic ramifications: if it's the first option, the Kohen should primarily concentrate on the tzaraat itself; if it's the second, he should focus on the lashon hara or whatever caused the tzaraat.
At the end of the day the two are linked, and I assume bedieved the korban would be valid anyway. I wouldn't call it a huge difference, but it's much larger than, for example, zeicher/zecher or lifneihem/bifneihem. Although changes of a letter have consequences for the validity of a Sefer Torah, I don't know of any other cases that result in a bigger change in meaning than this one.
- Where do the two versions come from, and what are the arguments in each direction?
- Does anyone specifically discuss the difference between them?
- Is the difference in meaning significant enough that if you read the wrong one, you are not yotzei?
- Have there been recommendations to read both? (I've never heard such a thing.)
(The practical aspect is moved here)