Many answers have been given to this. I'd like to share with you the answer of the Maharal, in his book "Gur Aryeh". He quotes from the Sifri (an old commentary on Numbers and Deuteronomy by Rav) that what is meant here is: "as fearless as Moses". He then explains this. If someone is repeating the word of G-d, then he will be fearless! If he is not fearless, it is not really the word of G-d, or at least he does not really believe it is. Such is the power and blessing which comes with the privilege of repeating the word of G-d.
This is a tremendous thought. If you are not fearless about repeating the word of G-d, you should search yourself. Either it is not really the word of G-d, or you do not really believe it yourself!
I have had interesting experiences in my Jewish education classes which seem to bear this out. Often when I have a new student, who knows nothing about Judaism, and the class gets involved in the intricacies of the laws of "muktzeh", or "sha'atnez", for example, and I'm afraid that this will turn the student off, and he or she won't come again, I find out later that it is precisely this that appealed to the student, rather than sweeping philosophical assertions about monotheism, or the nature of the Universe, for example. It seems here indeed that the words of the Torah, or the words of G-d, have a power and conviction of their own, and we need not be afraid of their effect. It is as if there is a match between these words and this Jewish soul, and I am just being the intermediary.
Now, with Rosh Hashanah approaching, the period when we should all be searching our souls to see what new mitzvos we can take on, and what old mitzvos we can strengthen, we should realize that what determines our behavior is not just our intellect, or even our emotions, and not even our spirituality, but, to a large extent, a fear of other people's reactions. It would help if we realized that the word of G-d carries its own power and conviction, and there is no reason to be afraid of it. You will generally find that the reaction of people will not be as negative as you had feared, and may even be positive, if you perform your new mitzvos with courage and sincerity. The only time you are likely to get a negative reaction is when you try to disguise your behavior, and pretend you are doing something different. Then people may get the impression (correctly!) that there is something strange about your behavior.
So from this weeks parsha we can learn that if we repeat, or carry out, the word of G-d, we have nothing to fear.