Do believers sin?

When I was a new Christian, I told another believer that I was struggling with controlling my temper. She told me that I was not a genuine Christian because if I was, I wouldn't sin. If she is right, not only was I not a Christian then — I still am not a Christian now. When you discover two very different interpretations of the Bible, how do you decide who's right?Most people fail at Bible study because no one ever taught them how. Bible Study Boot Camp fixes that: one short email a day for a week, plus a worksheet you can use on any passage for the rest of your life.Sign up for Bible Study Boot Camp