Unless I am mistaken, we have sufficiently proved that man is so held captive by the yoke of sin that he can of his own nature neither aspire to good through resolve nor struggle after it through effort. Besides, we posited a distinction between compulsion and necessity from which it appears that man, while he sins of necessity, yet sins no less voluntarily.
John Calvin - The Institutes of the Christian Religion 2.4.1
We are captive to sin and can only break free by putting our faith in Jesus as Savior (and hopefully as Lord of our lives as well). I truly believe that.
We are sinful by nature and want to sin deep at our core. I truly believe that.
So we sin by necessity of our captivity and voluntarily by our nature. I hate it when Calvin nails it dwon so firmly that I can only struggle like a butterfly pinned in someone's collection.
It is thinking along these lines that drives me back to Christ each and every day to seek His strength in overcoming what I am and what I am helpless to combat without my Lord and General.
I know many do not like Calvin and I can understand that getting hammered like this day after day as you read him is not most folks idea of fun. But the nuggets of truth buried herein, mined out and brought to the light of your day, can make you reflect on who you are, and more importantly who Jesus wants to be for you. Your Savior, your Lord, the General to lead you into battle against your sinful self.