Galatians 2:20 "I am crucified with Christ: nevertheless I live; yet not I, but Christ liveth in me: and the life which I now live in the flesh I live by the faith of the Son of God, who loved me, and gave himself for me."
Have you ever said or heard that statement? I sure have. I said it as a newborn believer. I remember saying it to someone once when God had showed me something from His Word through a message that had been preached. I remember saying I couldn't do whatever it was. That person (I can't remember who) told me that I was right. There was no way I could do that thing. But they kindly assured me that God would never ask me to do anything that He wouldn't equip me or give me the power to do.
The truth of the matter is that I can do nothing apart from Him. In fact....God isn't even as interested in what I can do for Him as He is that I allow Him to do it in me and through me. That was a banner time in my Christian life when that spiritual light bulb went on in my heart.
Once a person belongs to Him He will and can do anything in us and through us as long as we allow Him to. He just needs us to be willing. He has to be in control.
Romans 12:1 "I beseech you therefore, brethren, by the mercies of God, that ye present your bodies a living sacrifice, holy, acceptable unto God, [which is] your reasonable service."
So the next time you find yourself or someone else saying "There is no way I can live a Christian life" or "There is no way I can do that thing that God expects me to do" just remember Philippians 4:13 "I can do all things through Christ which strengtheneth me." Let Him do it in you and through you. You'll find it much easier when you quit trying to do it and let Him do it through you.