Dvar Torah Parshas Re'ah

Liyluy Nishmas Elchonon Tzvi ben R'Yisroel Meanachem........
In the first posuk in the parsha it says "R'aih anochi nosein lifneichem hayom bracha uklala" in the Medrash Rabah it says that the Rabanan say that Hashem was saying "i did not give you the brachos and klalos to harm you and to make things bad for you,rather I gave them to let you know the right way to act so you should choose that way,in order to receive schar" the Rabanan know this from the lashon of "R'aih anochi nosein lifneichem" The Rosh Yeshivah ztl asks that according to this medrash since the whole reason for the brachos and klalos is to tell you right from wrong,why is it necessary?Klal Yisroel already knows the right and wrong way to act because of all the mitzvos and aveiros in the Torah,so what are the brachos and klalos adding?He answers that without the brachos and klalos,klal yisroel would have made a mistake
 based on their negios and would end up mixing up right and wrong.Even when the Torah says straight out the mitzvos and aveiros,if Hashem hadn't mamash said what's right and wrong in the brachos and klalos,klal yisroel would have ended up doing the wrong things.The koach of negias are so strong,that someone can go so far as to thinkin that the aveiros that he is doin are really mitzvos!We ourselves have to work on ourselves to realize how negios affect us. We should try to look at things that we may be nogea to from more of an outside point of view in order to do what's right as appose to only what we'd like.
Good Shabbos!