"He that trusteth in his own heart is a fool: but whoso walketh wisely, he shall be delivered." -Proverbs 28:26, KJV

This verse starts off by telling us that we cannot even trust in ourselves. Even though we have been saved, we still have a sin nature (and, therefore, will continue to sin). Our hearts still want to go with the world, but we need to make sure to walk wisely by following the Bible. Even as we follow the Bible, this verse simply tells us that we will be delivered from sin, not that we won't want to do it. God knows that as long as we are in our fallen state that we cannot meet the requirements for holiness. He provided for us to have a Savior and gave us the Instruction Manual to learn to live. We won't ever be truly perfect until He calls us home to eternity with Him.