Psalm 119:4 Thou hast commanded us to keep thy precepts diligently.
While we can see the error of the Legalists on one hand and the Libertines on the other, we should never let such excesses paralyze our own due diligence in the pursuit of holiness. And, mind you, the pursuit of holiness cannot be rightly taken up without the Law of God, for it is the standard by which we measure our progress. Granted, we will only have gradual progress until that day the Lord returns and makes us like He is, but we are nonetheless charged to “keep [God's] precepts diligently.”
Do we love Jesus? Then we ought keep His commandments (John 14:15). Do we hate our sin? Then we ought diligently study the Law to see our sin in light of God’s perfection (Romans 7:7b). Do we love one another? Then we ought seek their good, for Christ’s sake (Exodus 20:12-17). Do we realize the exceeding sinfulness of sin? Then we ought see that the mortification thereof is more important than life or limb (Matthew 5:29, 30).
Christians have the privilege of possessing an alien righteousness that gives us a right standing before the Holy God of Scripture. In light of such a wonderful truth, is it really so difficult to believe that God expects, nay demands, our pursuit of perfect obedience to His Law? It shouldn’t be. Romans 12 calls it out “reasonable service.” Does this mean we can merit God’s favor by keeping His Law? Of course not, because even in our greatest law-keeping we are yet deficient. We don’t keep the law to merit favor, but as a response to undeserved favor lavished upon us.
Would that we can echo the Psalmist when he says, “O how love I thy law! it is my meditation all the day.”