The Christian life can be so complex — and oh so very simple.

That we would use such a fancy word as sanctification betrays the complexity. But that defining such a big word could be so easy hints at the simplicity.

Big Word, Modest Meaning

The word sanctification is built on the Latin sanctus, meaning “holy.” Sanctification is the theological term we Christians often use for the process of being made holy. For the Christian, whose standard of perfect human holiness is Jesus, the God-man, sanctification is essentially becoming more like Jesus — being “conformed to the image of his Son,” as Romans 8:29 puts it.

Christian growth, or maturation, is another way to define sanctification. It’s a big word for the little-by-little progress of the everyday Christian life. That much is simple. But what it encompasses is enormous: how every professing Christian should live, where our holiness is heading, how fast the progress should be, and how it happens in real life. Here’s where it gets complicated and controversial.

When Walking with Jesus Gets Messy

Sanctification talk gets prickly quickly because it immediately involves so many massive realities in the Christian worldview and their coming together in daily life: grace and works, law and gospel, faith and the Holy Spirit, Christian obedience and pleasing God, love and good deeds, and much more. And sanctification gets very personal — it’s about the details of your life.

The stakes are high. Weak spots in our theology will turn up, before long, in our understanding, and pursuit, of sanctification. It doesn’t take much time before a wacky doctrine elsewhere begins to mess with our doctrine and practice of holiness. True Christian theology is a seamless garment, and every doctrine eventually relates to every other, but sanctification seems to call the question faster than the others, and has the tendency to accentuate our problem areas.

Beware a False Simplicity

Because of the inherent complexity of sanctification, involving all these moving pieces, there is a great temptation to oversimplify things. Because sanctification with all its tentacles feels like an octopus larger than we can comfortably tame, we tend to prefer our own little theological house pets that we can easily train and remain captain of. It’s nice to have a slogan that can keep it simple for stupid humans and make us feel like we’re in control.

Enticing as it sounds — and convicting as it may be to hear about if you’ve tried it — the well of sanctification reductionisms soon runs dry. “Let go and let God” — it won’t be long before that creates some problems. “Simply obey” — that won’t do it either. “Just get used to your justification” — attractive, yes, but there’s another reductionism at work here. Even “union with Christ as the key,” close as it may be, falls short of capturing the full picture.

No Silver Bullet

It’s as if we find the biblical data to be just too numerous and complicated, and what we really need is to search for sanctification’s holy grail. It must be out there somewhere — surely, there’s some quick fix, some theological secret to discover, some doctrinal key that unlocks what holiness really is and how to have it.

But if there’s any key to sanctification, it’s this: abandon your search for the key. At least abandon the search for a shortcut. Let your quest for the holy grail of sanctification end right here and right now, and commit to a sanctification not of only, but of all — all the Scriptures, all of Christian theology, all the Bible’s salvific pictures, and, ultimately, all of Jesus.

Embrace the Complexity

What is needed for Christian sanctification is not some silver-bullet doctrine or fresh slogan or new overriding emphasis, but the whole of the Bible, theology, and Jesus. The same Jesus who is our righteousness for justification is the same Jesus who is our holiness for sanctification — and is the same Jesus we’re united to by faith to receive all God’s priceless graces.

By virtue of our Spirit-powered, by-faith union with Jesus, we have the new-creation spiritual life of regeneration, and the righteousness of justification, and the holiness of sanctification, and the familial affection and privilege of adoption, and the honor of glorification. This is big. It gets complicated. There are so many ducks that it’s hard to get them all in a row — and that’s just the way God would have it. After all, he is the sanctifier, not we. He would rather we always lean on him for holiness than supposing we have it figured out.

With a Singular Focus

But even in all the complexity, there is a point of focus that can help us get our bearings and give us some semblance of simplicity. The beginning and end of Christian sanctification is none other than Christ himself. There is an initial relationship with Jesus that first sets us apart as definitively sanctified, and gets the gears going for our ongoing sanctification, but a deepening relationship with Jesus is the heart of sanctification, and knowing Jesus is the great goal of our sanctification.

Jesus is not only the preeminently sanctified one and the one who empowers our sanctification by his Spirit, but also he is the one whom the whole of our sanctification is shaping us to know forever (Ephesians 5:26–27). Knowing Jesus drives us onward in sanctification now (Philippians 3:8), and knowing Jesus is the eternal life that sanctification fits us for (John 17:3).

This One Great End

The greatest blessing of salvation is not mere forgiveness. It’s not just justification and being declared righteous. It’s not new birth. It’s not even sanctification. It’s not just the privilege of being united to him, but being united to him serves the greater goal of enjoying him.

The greatest blessing of redemption is Jesus himself. All aspects of the Spirit’s subjective application to us, and all of Jesus’s objective accomplishments for us, conspire to this one great end: knowing Jesus, enjoying Jesus, admiring Jesus, and treasuring Jesus for all eternity.

David Mathis writes on “The Search for Sanctification’s Holy Grail” in Desiring God’s newly available Acting the Miracle: God’s Work and Ours in the Mystery of Sanctification, which includes contributions from John Piper, Kevin DeYoung, Ed Welch, Jarvis Williams, and Russell Moore. The book is now available in softcover, as well as a free PDF, from Crossway Books and Desiring God.