The Rambam[1] rules that one who utters HaShem’s Name in a sh’vuat shav[2] or a beracha l’vatala[3] violates the Torah prohibition of using His Name in vain. One who utters His Name without a purpose transgresses the lower level Torah commandment to fear His Name.[4] In the latter case, the Rambam instructs one to rectify an improper utterance of the Name by adding words of praise to HaShem.
The gemara[5] discusses which sacred texts a ba’al keri[6] may recite. One opinion allows him to engage in normal talmudic study as long as he does not utter HaShem’s Names in the process. Rav Yaakov Emden[7] proves from here that people other than a ba’al keri may pronounce the Names normally, at least when reciting p’sukim that contain a Name. He related that his father[8] scolded teachers who refrained from the real pronunciation of the Names during learning. (We are referring to the standard reading of A-D-O… for HaShem’s four letter Name, not a literal reading of its letters.)
There are several attempts to deflect Rav Yaakov Emden’s proof, but they are not convincing.[9] The Mishna Berura[10] thus rules that one may pronounce, in the normal manner, the Names found in the p’sukim one reads from the gemara. However, the Igrot Moshe[11] points out that although one may pronounce the Names, there is little indication that he must do so. He argues that the only reason to mandate proper pronunciation is that it is improper to end a quote of a pasuk in the middle, and effectively omitting a Name from a pasuk by altering it may be the equivalent. (We are unable to develop that topic in our present context). However, if one is not reciting an entire pasuk anyway, as is common when learning, he may replace the main Name with “HaShem” (which means “the Name”) and change other Names.[12]
The Shulchan Aruch[13] says that children may recite the exact berachot they are learning, even while just practicing. The Magen Avraham[14] infers that when an adult learns a text that contains a beracha, which is more problematic than a pasuk, he may not mention the Names. What about tefillot that are not in the form of a formal blessing? The Rama[15] says that if one omitted Ya’aleh V’Yavo in Birkat HaMazon on Rosh Chodesh, the correct procedure is to not recite it later because it contains HaShem’s Names. The Magen Avraham[16] disagrees, pointing out that we use His Name in personal prayers even when not obligated. The Bi’ur Halacha[17] reconciles the apparently contradictory practices. One may, on his own, invoke HaShem’s Name in prayer when he does so voluntarily; one may not recite an established, obligatory tefilla like Ya’aleh V’Yavo when it is unwarranted.
As alluded to in the aforementioned Rambam, it is likewise permissible to use HaShem’s Name in praising Him, including in Shabbat zemirot and other liturgy. Indeed, some talmidei chachamim pronounce the Names in the normal manner.[18] The rhyme scheme of some zemirot indicates that the liturgist also did so. However, many have the custom to alter the pronunciation.[19] The explanation for this custom is apparently that we are concerned that we will not have the proper frame of mind,[20] we may stop in the middle of a phrase,[21] or we may otherwise disgrace the Name.
In practice, one can choose either the normal or the modified pronunciation of HaShem’s Names when reading Torah texts, saying informal prayers, or singing zemirot. However, when studying berachot, one should use the modified form, and when reading a whole pasuk, it is proper to pronounce the Names accurately.