On: every psalm and song in the daily prayers uses today’s English. Off: all of them use the older “thee and thou”. Until you choose, the Songs of Zechariah, Mary and Simeon use today’s English, as most churches sing them. The Lord’s Prayer and the prayers for the dying show the form most people learned.
The complete confessional writings of the Lutheran church, published on the fiftieth anniversary of the Augsburg Confession: three ecumenical creeds, the Augsburg Confession and its Apology, the Smalcald Articles, the Treatise, both catechisms, and the Formula.