If salvation was just belief I think most of us would have no problem believing we are all saved. But I think it has two legs. Salvation and repentance. How would you be working out your salvation with fear and trembling if you just had to believe? No, there is this requirement I think that you keep growing at all times. If you aren't getting closer to God, you are going further away.
I can't find it now but I remember reading, maybe in Jeremiah, where God says if a man does good all his life and then screws up God will judge him and if a man does evil all his life but then does good, God will reward him. There is no kicking back in this life. God requires our all and to endure to the end or we don't get our reward.
So I press on.