In re Michelle's article at http://www.fivedoves.com/letters/may2013/michelle526.htm on the dating of Mount Sinai, here 's a very LITERAL translation of the Hebrwe text from Exodus 19:1

א  בַּחֹדֶשׁ, הַשְּׁלִישִׁי, לְצֵאת בְּנֵי-יִשְׂרָאֵל, מֵאֶרֶץ מִצְרָיִם--בַּיּוֹם הַזֶּה, בָּאוּ מִדְבַּר סִינָי.

1 In the third month after the children of Israel were gone forth out of the land of Egypt, the same day came they into the wilderness of Sinai.

The Hebrew calendar runs:

1. Nisan
2. Iyar
3. Sivan
4. Tammuz

They left Egypt on Passover Day, Nisan 15, without any question.  By "third month", does that mean the third calendar month, Sivan?  Such an interpretation would still leave ambiguous as to whether they meant Sivan 15 or Sivan 1st or anytime in Sivan.  It could mean as soon as the month turned to Sivan.  That would make sense.  Especially since "Chodesh" can refer to the first day fo the month as much as the month itself.

 OR does it mean the third month with exclusive or inclusive counting counting in time sequence from leaving Egypt.  Inclusive counting would suggest therefore Sivan 15 or sometime in that month.  Exclusive counting would suggest Tammuz 15 or sometime in that month.

Jewish tradition interprets this as Sivan 1, and believes that the giving of the Law on Mount Sinai (which means "The Mountain of Temptations") Happened 50 days after Firstfruits, or on the festival of Shavuot (Pentecost), usualyl celebrated on Sivan 6 on the Jewish calendar.

 

Shalom,

Joe