For Luther the Bible consisted of the texts of the Old and the New Testament which he knew from the Vulgate (the Latin Bible translation). Luther engaged in lectures, sermons and translations during his whole life. Especially the Epistle to the Romans was important to Luther, because he derived from this his doctrine of justification.
From his time in the monastery of Erfurt it is known that Luther was engaged intensively in study of the Bible. Luther was engaged in the Psalms in monastery prayers, and as a student he was engaged with Bible study. He knew Hebrew (rather poorly) and later on Greek, through which Luther could read the Bible in the original languages. In his lectures on the Psalms, the Epistles to the Romans, Galatians and Hebrews he used this linguistic knowledge. Through the philological studying of the righteousness of God in Romans 1:17, Luther found that here is not meant an active (demanded), but a passive (given) righteousness. God gives this passive righteousness to people by faith. The image of God and the Hermeneutics of the Bible were changed by Luther through this discovery. The Epistle to the Romans became the key for the whole Bible. Luther distinguished between central texts, such as Romans, John and Galatians, and less important texts such as Hebrews, Jude and James. He put James in the back in his translation of the New Testament. Luther read the Old Testament in a christological way, where he saw the Old Testament mostly as law. He placed several books of the Vulgate under the apocrypha.
Luther took pride in his translation of the Bible. In 1521 he started translating the New Testament in German at the Wartburg. He was ready with this in September 1522. His New Testament sold like hot cakes on the book market and in December 1522 they needed a second edition. He took a longer time to translate the Old Testament. However, in 1534 it was possible to publish the whole ‘Luther Bible’. The principe of translation adopted by Luther was that he did not abide precisely by the text, but he searched for the goal of the text and he tried to represent this in the best contemporary German. Luther received criticism because he added words to the text by himself, such as the word ‘alone’ in Romans 3:28. He was involved in an intense competition, because also other scholars published Bible translations as well. However, their original text was the Vulgate. In translating, Luther was supported by colleagues from the University of Wittenberg. Luther kept very precise watch over his Bible translation; he left records on where images were allowed to be inserted. He revised the text at the end of his life in 1544-1545, but sometimes these corrections were not implementeed. This was because the edition was published after Luther’s death in 1546, and thus it could not be checked for Luther’s revisions. Elector Johann Frederick the Magnanimous supported Luther’s edition, and he took care that the edition from 1524 was protected from plagiarism and robbery. However, this was impossible to prevent.
The Word of God in the form of the Holy Scriptures was for Luther a treasure which was the standard for all theological pronouncements and the whole of life. For Luther, the Bible stood above the tradition of the church. The Bible explains itself to the believer and there was no need for an institute that determined what the right explanation of the Scripture was, though later in life Luther would come to regret his earlier opinion given the appearance of the ‘Schwärmerei’. Preaching was the method by which to pass on the Word of God.