Perhaps you have heard of C.S. Lewis. He ranks among the most admired and quoted writers of our time. In his youth, he was an atheist. Later, this brilliant Oxford professor abandoned atheism and converted to Christianity.
As an atheist, he admitted there were times when his atheism did not seem very probable. And after his conversion to Christianity, he said there were times when Christianity seemed improbable. In others words, there were times when his faith in atheism and in the Christian faith waivered. Thankfully, when he died in 1963, he died praising Jesus Christ.
We are saved by grace through faith in Jesus Christ (Ephesians 2:8, 9). We are not saved by our works. Our faith does not save us. Jesus saves us. Faith means to believe what God has promised. Again, my faith in Jesus does not save me. He saves me. And, according to Philippians 1:6, once God begins a good work in our lives, He will see that work through to its completion.
I am saved by Jesus. And Jesus will make certain that I remain saved. It is not about me. It is not about what I do. Me? I am just the dummy along for the ride! It is all about Him, what He has done, and what He will continue doing.
This is so simple. I am a sinner. I sin. Jesus is the Savior. He saves. I did my part, and now He is doing His part.