Of course the opposite is true as well: more justification preaching means more sanctification. But this statement needs to be qualified while the other one does not.
The fact of the matter is that all confessional Lutherans want Christ to be proclaimed. And we want the message that God justifies the wicked in Christ to be heard more and more – and for failing Christians more and more.
That takes more sanctification. And I think all of us know it.
I know people balk here, so please listen to what I recently told someone: when I make statements like “all of us judge some to be more holy than others” I am thinking about others, not myself. I am a complete and total mess. My pet sins and terrible attitude (I am the father of 5 boys under 10 and I don’t handle it very well, I think) disqualify me from any serious consideration of being highly sanctified. I am not consistently driving old Adam out, in the power of the Holy Spirit, like I should be. Somedays it is like I’m just a sleepwalking old Adam, permeated by original sin, unable to shake the bad attitudes and habits, and seemingly unable to look to God for help in overcoming the sin that seems to utterly possess me.
So what to say? Perhaps this: Wretched man that I am! Who will deliver me from this body of death? Thanks be to God through Jesus Christ our Lord! So then, I myself serve the law of God with my mind, but with my flesh I serve the law of sin. There is therefore now no condemnation for those who are in Christ Jesus.