Salvation by grace alone

You might think that the clarity given to this subject throughout the Bible, and in particular in the verses chosen, would make it clear that salvation is by grace alone, yet there is and has been a vicious debate over this subject since the fall of Adam in the garden.
We often think that we fight this battle alone, yet I submit to your thoughts today, that this age old epic battle has been going on since and Adam and Eve sewed fig leaves together in the garden to try and cover their sin.