“For though I made you sorry with a letter, I do not repent, though I did repent: for I perceive that the same epistle hath made you sorry, though it were but for a season. Now I rejoice, not that ye were made sorry, but that ye sorrowed to repentance: for ye were made sorry after a godly manner, that ye might receive damage by us in nothing. For godly sorrow worketh repentance to salvation not to be repented of: but the sorrow of the world worketh death.”
2 Corinthians 7:8-10
Because we desire to be more like Jesus, we make resolutions, ask Him to help us, and try to behave differently. Yet despite our best efforts to do things God’s way, we slide back into old habits 
Frustrated, we may ask Him, “Why can’t I change?” The reason is, overcoming sinful attitudes and behaviors starts with genuine repentance, which has three aspects 
Conviction. The Holy Spirit will reveal the areas in which we’ve sinned and convict us of wrongdoing. Through Scripture, the Spirit shows us God’s standard and what needs to change. Repentance begins with understanding where we have gone astray.
Contrition. The next step–grieving over our iniquity–is followed by confession to the Lord. Genuine sorrow arises from the knowledge that we’ve sinned against Him. In contrast, human unhappiness often comes from being caught misbehaving. Other times we are miserable because of where our choices led us, or feel shame that people know about our sin. True contrition is followed by humble confession.
Commitment To Act. Real repentance is complete when we wholeheartedly pledge to turn from our old behavior and move toward righteous ways. God knows we won’t live perfectly, but He looks for a surrendered heart that diligently seeks to obey Him.
Paul used strong language when telling us to turn from iniquity:“Mortify therefore your members which are upon the earth…” (Col. 3:5). What sin are you struggling to overcome? Have you genuinely repented, committing to turn from it permanently? Let the Holy Spirit empower you to change 
Source: http://www.crosswalk.com
