No modern "priesthood of all believers" in Luther

Not the phrase:  "There [a]re no references to this phrase anywhere in Luther's own writings.  'Das allgemeine Priestertum aller Gläubigen,' in all of its Latin and German permutations[, i]s nowhere to be found" (1).

Not the doctrine, understood as the sort that would justify (except in the very rare case of a true emergency) the assumption of a supposed ministerial "function" on the part of an unordained member of the Christian community.  Luther reduced the two (e)states (Stände) to one, the single, baptismally-generated spiritual state of priestly existence (Priestersein, in the felicitous phraseology of Harald Goertze and Wilfried Härle (TRE 27, 402-410, as quoted at 13n16)), but refused to compromise when it came to office (Amt), which is much more than an interchangeably exercisable "function":  "'all Christians are truly part of the spiritual walk of life [Stand], and among them there is no difference except because of the office [Amt] alone'" (WA 6, 407, ll. 13-19, as quoted at 9, italics mine).  "a single Christian walk of life (Stand) and a variety of offices (Ämter)" (30).  Proper ordination is therefore required.  “our baptism may consecrate us as priests [(pfaffen, pffeffyn)] but does not authorize us to exercise the pastoral office” (16 & 23, italics mine).

     It is rather in Spener that we "find the first serious discussion of the category [('the Spiritual Priesthood,' 'deß Geistlichen Priesterthums')] though not the term itself," and in Pietism that the term as well as the doctrine appear.   And it is from there that it wormed its way into the assumptions that nineteenth-century specialists made about Luther (2 ff.).

     Timothy Wengert, “The priesthood of all believers and other pious myths” (2005).  See also http://scholar.valpo.edu/ils_papers/117/, and Saying and Doing the Gospel Today, ed. Rhoda Schuler, Occasional Papers, no. 12, of the Institute of Liturgical Studies (Valparaiso, Indiana: Institute of Liturgical Studies, 2007), 92-115.