Any "binding" that you put in there (works/obedience with salvation) makes in not a free gift, and therefore not by grace through faith. When you get Christmas presents, how would you feel if there was a note inside each one that said: "You only get to keep it if you do _____________" ? That's not a free gift, that is, it would not be true grace.
On the contrary! It is the adopted sonship that is the free gift. The obedience is our response to that free gift. My obedience (what little there could possible be) is worthless outside of being Christ's adopted brother, but IS of value when performed by a member of His family. I suspect that this is the answer to the dilema some have reconciling James 2 with Paul's doctrine of Faith.