Shavua Tov. Today's פרשת נשא, discussed the Nazir, who abstains from drinking wine and cutting his hair. At the end of his period of Nazir, he offers a sin offering. Most commentators say that this is because he took too many laws upon himself.
Shimon Hatzadik was Kohein Gadol for forty years and only offered one Nazir sacrifice.
A story is told that a very handsome man saw his reflection in the water and realized for the first time how good looking he was. He became frightened that he would sin because of this. He decided to become a Nazir and was praised by Shimon Hatzaddik for his sincere efforts to stay away from sin.
We must also try to protect ourselves from sin in every situation.