Pronouncing Hashem's name in a song

Some people are very careful to say Hashem or Elokim when singing a song with one of G-d's names in it so as not to use His name in vain (related question), but I have also been told this is unnecessary since these songs are equivalent to prayer.

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  If you shouldn't pronounce them, why did the authors put them in explicitly?

  
  


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  If there's no problem with pronouncing them, then how does repeating the words (for example, in the chorus) affect that? I mean, now that you're saying the words simply to fit in with the melody does that make pronouncing them in vain?

  
  

Answer

http://www.ou.org/torah/tt/5766/miketz66/specialfeatures.htm

Rambam (Sh'vuos 12:9) rules that one who uses Hashem's Name in a meaningless oath or a an unwarranted blessing violates the Torah prohibition to use His Name in vain. One who utters His Name without a purpose transgresses the lower level, Torah commandment to fear His Name (ibid.:11).In the latter case, the Rambam instructs one to rectify an improper utterance of the Name by adding words of praise of Hashem.

As the aforementioned Rambam hinted, it is likewise permissible to use Hashem's Name to praise Him, including in Shabbat zemiros and other liturgy. Indeed, some (incl. Rav Sh. Z. Orbach) pronounce the Names normally. (The rhyming in some zemirot indicates that the liturgist also did so.) However, many have the custom to alter the Names (Nefesh HaRav, pg. 160 reports that Rav Soloveitchik did not utter the Names in zemirot). The explanation of this custom is apparently that we are concerned that we will not be in the proper frame of mind (B'tzel Hachuchma IV, 52) or may stop in the middle of a phrase (see Igrot Moshe, ibid.) or otherwise disgrace the Name. [Ed. or overly repeat phrases in singing the Z'mirot.]

In practice, one can choose either to pronounce normally or change Hashem's Names when reading Torah texts, saying informal prayers, or singing zemirot. When studying b'rachot, he must change the Names; when reading a whole pasuk, it is proper to pronounce the Names accurately.