Holiness is related to the idea of wholeness, completion. God is holy, holy, holy – not only in His purity and light, but also in His perfection, His completion. He is holy because there is no shadow of turning in Him. He is not missing anything. He is all that He is. He is the great “I am.”
This means that holiness is not merely putting off sin and putting on righteousness – though it is certainly that — but that very process of becoming holy is also becoming what you are. Pure holiness is being who you really are, who God made you to be in Him.
And that in turn makes holiness more concrete, more practical. Holiness is not opposed to nature. Salvation is God’s gracious healing and glorification of nature. This includes your nature, your body, your sex, your personality, your gifts and abilities. Being holy as a man means growing in your masculinity, taking initiative, responsibility, learning to sacrifice in love. Being holy as a woman means growing in your femininity, cultivating fruitfulness, beauty, and wisdom. Holiness is not gender neutral or some kind of Zen state of mind. Holiness is Spirit-empowered obedience in your particular circumstances.
Sin is that which steals and destroys God’s good creation. It mars nature. It defaces the image of God in men and women. Therefore, temptation to sin is always an invitation away from what God made you to be. Temptation to sin is always an offer to become someone else, something else than what God created you for. Sin is becoming what you are not. Holiness is becoming more of who you really are in Christ.
But who you really are is found in the One who already is who He really is. God is complete, perfect, whole. And He is infinitely whole. This is why He is the only one who fills all things, the only One who can complete and perfect everyone. No creature has that capacity. But as we look to Him through Jesus Christ, we are being changed from glory into glory. We are the sons of God, and it does not yet appear what we shall be: but we know that when he shall appear, we shall be like him; for we shall see him as he is (1 Jn. 3:2).