Faith, Works, Salvation, Grace are all seperate issues with seperate consequences.
What on Earth are you talking about? Salvation is separate from Grace? Grace is separate from Faith and Works? Read the Scripture: "Not every one that saith to me, Lord, Lord, shall enter into the kingdom of heaven: but he that doth the will of my Father who is in heaven, he shall enter into the kingdom of heaven."
We obtain Salvation through the Grace of God. We cannot earn Grace. Grace is a gift to us through Christ. We accept that gift through Faith and Works. It is really just that simple.
I'm going to start backwards here.
Why did Yeshua have to take on our sin? Because there is NOTHING we could do gain salvation. Is there a work you can think of which earns you salvation?