Psalm 51

is appointed in the LSB Psalm chart for daily prayer during the General season twice in a month:  Friday morning of the first week; Monday morning of the third week.  Something about this Psalm that I'd not noticed before:  "then."

Restore to me the joy of your salvation, and uphold me with a willing spirit.  *Then* I will teach transgressors your ways, and sinners will return to you.

Then?  The *then* of teaching transgressors the ways of the Lord, the *then* of their return to the Lord, hangs upon the restoration of joy in God's salvation which upholds the believer with a willing (free) spirit.  In other words, joy in salvation is the foundation from which proceeds "evangelism."  If we, if our people, are not teaching transgressors and if sinners are not returning to the Lord, perhaps it is not for lack of technique or marketing expertise on our part?  Perhaps it is always that we and our people need to be restored to the joy of God's salvation!

For what you ENJOY, that you natively PRAISE to others.  We do it all the time!  "You've GOT to read this book, see this movie, eat at this restaurant...."  So, the Psalmist would teach us that the key to witnessing to the Gospel is first to taste and see that the Lord is good, and that blessed are those who trust in Him!  The key is to drink deep until it fills us and we can't not be recommending to others the joy that we have found in God's salvation:  unspeakable grace, the forgiveness for sins, the promise of a life stronger than death, a heavenly Father's love, an eternal inheritance kept for us, the companionship of the holy angels, the unspeakable peace that comes from communion with Father, Son, and Holy Spirit.

Then, then, then, I will teach transgressors your ways!  For David, that meant that even after the horror of his sins - his adultery, murder, and lies - after it all, God still didn't throw him away.  But loved him, forgave him, kept him as His own.  Grace unspeakable, joy abounding.  Then, then, then, I will teach transgressors your ways!  When you see that you haven't been tossed away either - but welcomed, loved, embraced - and above all provided with a Redeemer for your sins and a Comforter to constantly write the faith-giving promises in your heart.  Evangelism lives on the other side of that.  It's St. Paul's "if he could have mercy on the likes of ME, don't you be despairing!"