Wikipedia — Four senses of Scripture
Concordia University — The 500th Anniversary of the Reformation — Luther and Biblical Interpretation
Luther identified the shortcomings of this approach, which was too often dependent upon guesswork and the whims of the interpreter. He wrote, “It was very difficult for me to break away from my habitual zeal for allegory. And yet I was aware that allegories were empty speculations and the froth, as it were, of the Holy Scriptures. It is the historical sense alone which supplies the true and sound doctrine” (LW 1.283).
Luther identified that the Scriptures had one sense, the literal or natural sense. This did not mean that he was a complete literalist. For example, he stated that figures of speech are meant to be taken figuratively. However, when the Scriptures speak plainly, they should be taken literally according to the normal use of language. The implication of this approach is that the Bible is clear in its meaning and can be understood by ordinary people.
Luther again reflects on his development of thought concerning exegesis “Now I have shaken off all these follies, and my best art is to deliver the Scripture in the simple sense; therein is life, strength, and doctrine; all other methods are nothing but foolishness, let them shine how they will . . .” (Table Talk CCEL 275).
To illustrate the defects of allegorical interpretation, Luther compares it to the legend of St. George: St. George is Christ, the woman he saved is Christendom, dragon is the devil, the horse is the human nature of Christ, the spear is the gospel message, and so forth. Allegorical interpretation is a “trifling art,” and here Luther does not mince words: “their interpretation is so stupid that it makes one feel like vomiting” (188). Such interpreters “juggle and play” with the texts, and as long as they do not damage the message of Christ, Luther is content to leave such “prophets,” as he sarcastically calls them, alone, but, Luther adds: “But when one examines it under the light and according to the text, it is revealed as pure jugglery. Devoid of foundation or truth, it is the product of his [Karlstadt’s] own fancy, and forced upon the text” (189-90).
(other pages within this blog talking about very similar things)
Trinity International University — Luther’s Allegory of the Three Doves
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Reformed Journal — Believing the Bible
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This helps us better understand Luther’s method of interpretation. Luther is critical of the church’s tendency to allegorize scripture. The church had developed a fourfold method of interpretation, which included the literal – historical, but preferred the allegorical / spiritual. Luther wanted to return to the literal historical as THE interpretation of scripture through which the spiritual message is proclaimed. But this isn’t a hyper literal approach, it’s a way to read the spiritual message of scripture in the plain words.
(I should come back and read this, there's some interesting bits here)
Union Publishing — The Reformers' Hermeneutic: Grammatical, Historical, and Christ-Centred
To read the scriptures with a grammatical-historical sense is nothing other than to read them with Christ at the centre.