Jonas was busied in conferences  and Augsburg ) and visitations during the next twenty years, and in diplomatic work with the princes. In the autumn of 1531, Jonas published a German translation of the Apology of the Augsburg Confession and in 1541 he began a successful preaching crusade in Halle, becoming superintendent of its churches in 1542 or 1544 and priest in the Market Church of Our Dear Lady  the city of Halle, Saxony-Anhalt. Martin Luther became severely ill and visited his friend during Christmas in 1545. Jonas was present at Luther's deathbed at Eisleben, and preached the funeral sermon; in a procession Luther's body was taken to Halle and buried in Wittenberg. In the same year Jonas was banished from the duchy by Maurice, Duke of Saxony. From that time until his death, Jonas was unable to secure a satisfactory living. He wandered from place to place preaching, and finally went to Eisfeld, Thuringia , where he died, aged 62.

Based on the above article, answer a question. How many years after Jonas published a German translation of the Apology of the Augsburg Confession did he begin a preaching crusade in Halle?
10