“I confess that I cannot forbid a person to marry several wives, for it does not contradict the Scripture. If a man wishes to marry more than one wife he should be asked whether he is satisfied in his conscience that he may do so in accordance with the word of God. In such a case the civil authority has nothing to do in the matter.” – Martin Luther (De Wette II, 459, ibid., pp. 329-330.)
So much for “Sola Scriptura.” Looks like we may actually need the Church for this one. Poor Martin just could not figure it out!