Dane Ortlund has a great section in his book "A New Inner Relish" on the topic of obedience. He writes:
"It is simplistic to see only two possibilities regarding faithfulness to God: disobedience and obedience. Rather, three options are before us: disobedience, authentic obedience, and inauthentic obedience. Disobedience refers, of course, to rejection of the imperatives of God. Inauthentic obedience is a bit more slippery. It is obedience driven by something other than the heartfelt love for God and His glory that characterizes authentic obedience.
Legalism, for example, sees obedience as a cause of fellowship with God rather than its result. Such 'obedience' is in fact disobedience, since God not only demands that we obey but that we do it for the right reasons (Deut. 28:47; Prov. 16:2, 1 Cor 4:5). So there is not only an external (the act of obedience) but an internal (the motivation) element of godly living.
We find ourselves, then, not with two kinds of obedience and one kind of disobedience. Rather, there are actually two brands of disobedience - one involving open defiance and one involving apparent obedience accompanied by impure motives - and only one true obedience."
How is your obedience to the Lord? Is it motivated by a heart of gratitude for what Christ has done? We must never separate the gospel's work from the call to obey or we will produce horizontal obedience that fails to bring glory to Christ. It looks like the real thing on the outside, but its an imitation of the real thing.