You can! Though the power of evil is very strong and you may personally feel very weak, the Bible teaches us that God will graciously give us everything we need to be able to live a life that pleases and honors Him (2 Peter 1:3-4).
This does not mean, of course, that we will never sin or do anything wrong. But it does mean that God will truly help us to live a life that honors Him, glorifies him, and pleases Him--if we genuinely and sincerely desire to live such a life and prayerfully seek to walk with Him every moment of every day.
Many Christians, however, continue to emphasize their weaknesses and failures and the power of evil in the world. What they say may be true, but when emphasizing the negative, they often neglect or minimize those many passages in the Bible which tell us of the grace of God and the power of God and the victory which He promises to give to those who humbly seek to serve and honor Him.
If we continue to emphasize the negative, we will probably not pray with the confidence that God will really help us life a life that is pleasing to Him. In fact, we may even get to the point where we actually expect to fail! And, after a while, we may not even be very concerned about our failures any more since we simply resign ourselves to the idea that "no one can ever please God anyway.”
Therefore, we begin with an emphasis on the positive teachings of the Bible concerning holiness and obedience. Though only Jesus perfectly and always did the will of His Father in heaven, we will find that there are many other people in the Bible who are commended for their lives of trust and obedience. And, in addition, we will find that the Bible provides us with many promises and some wonderful encouragement as we humbly and sincerely seek to Walk With God!
(From Walking With God By Dr. Edwin D. Roels)