I thought my post addressed that. If you have a TRUE faith you can see that by your works. Hence the obvious bad choice of the word ‘by-product’. I don’t know why this is tripping you up. Let me explain it a different way…
Our free will leads the choices we make. Free will basically means that neither God nor Man forces you to make certain choices. When faced with a decision we make the choice, whether good or bad, of what we feel we must make. Each path leads to a certain destination. Regarding Faith you are faced with MANY choices. Our free will lets us choose the faith we feel is the right path. God does not force us to choose Him. He will prod us and lead us but He won’t make us choose Him over another if that is not the choice we want to make. Right? Ok, so these choices, in regards to Faith, will affect our hearts in how God sees us. If we choose Him we will have a faith that urges us to do His perfect will. There is still free will, we can choose to ignore the Holy Spirit but, if we have TRUE faith that is hard to do as I am sure you know. If this is the case God can see that our hearts are truly for Him, alone. BUT if we choose another path that leads away from Him our hearts will reflect this and be hardened and He will see this also. Now, there are those who have chosen the path that leads away but for some reason, whether internal or external, they want to LOOK like a christian and will try to fool us and God by professing Him to be God of all BUT they don’t actually believe it. And that is evident by their fruits. Our works, or the things we do, are the FRUIT of our Faith.