“If we obey God, we must disobey ourselves; and it is in this disobeying ourselves, wherein the hardness of obeying God consists.”
Tchividjian, Tullian (2010-04-23). Surprised by Grace: God's Relentless Pursuit of Rebels (p. 38). Crossway. Kindle Edition.
I know that it this quote might seem out of place, because many times people who focus on the gospel are seen as "antinomian" (against the law). But that should not be the case. Ours is just a different perspective on the impetus that drives our obedience. Rather than seeking to draw approval to ourselves, we respond because of a deep vision of the beauty of the grace of God through Christ.
So we seek to obey. On the outside, it looks the same as anyone else's obedience. Much like the two houses in Christ's parable of the wise and foolish builders look the some on the outside. But while one seeks to draw approval (the house on the sand), the other clings on the grace and mercy of the cross, knowing that no amount of works will justify us or curry any favor from above (the house on the rock).
And I thought those sand houses were always full of non-Christians. Yet if they were, the houses wouldn't look the same on the outside, would they?