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.
Careful reading that draws meaning out of a text, attending to its language, form, and historical setting. Contrasted with eisegesis, reading one's own meaning into it.
In Scripture — The canon, translation, and how Lutherans read the Bible.