Shmos – 4:1 – And Moshe answered and said they won’t believe me and they won’t listen to my voice because they will say that G-d did not appear to you
Gemora: Shabbos 97(a): They won’t believe me – Resh Lakish says one who is suspicious of innocent people will be stricken in his body as it says “And Moshe answered and said they won’t believe me” And afterwards Moshe was stricken in his body as it says (in Shmos, Chapter 6) “and Moshe’s hand was leprous, white as snow”
Torah Temimah Colloquial Translation on Note #1:
It explains in the Gemora that it was revealed to G-d that the Jews would believe Moshe. So, G-d told Moshe that the Jews are “believers, the children of believers”. This is proven because it says about the Jews “and they believed” <need to quote the source for this> and it says about Abraham in Parshat Lech Lecha “he believed G-d”.
Yet the language of the Gemora here seems more wordy than it needs to be. It should have said simply that Moshe said they wouldn’t believe him and, in fact, they did. It is possible that the long wording is necessary because from this incident alone it is not possible to say that they are “believers, the children of believers”. In this case, the reason why they believed in Moshe was because of the signs and wonders that he demonstrated to them and also because of the special words that Moshe used when telling the Jews that he had come to redeem them. These special words are explained by Rashi in his comment on Shemos 3:18. Because of these special circumstances of the signs, wonders and special words, the Jews believed Moshe. However, G-d [who is All-Knowing] knew that despite this, the Jews are “believers, the children of believers” and would have believed Moshe without all these. The explains the longer wording in the Gemora.
The reason why Moshe needed the signs and wonders in addition to the special words was not for the sake of the Children of Israel but rather for him (Moshe) because he was worried that they wouldn’t believe him. Therefore, G-d gave Moshe the signs and wonders in order to ensure that Moshe would accept to go on the mission.
DBS Note: PLEASE CHECK OUT an amazingly similar comment that the Gemora makes on Genesis 18:4. The link for that article is here: http://temimahblog.com/?p=33