I came across this quote attributed to Luther; not sure of its veracity or source, but I like it. It sounds like something from the Table Talk:

Around 1530, Martin Luther expounded the qualities of a good preacher and contrasted those qualities with those of a preacher as the world would have him. First, as the world would have him, six things are necessary to the preacher: (1) He must have a fine accent. (2) He must be learned. (3) He must be eloquent. (4) He must be a handsome person, whom hte girls and young women will like. (5) He must take no money, but have money to give. (6) He must tell people what they like to hear.

And now, the true qualities of the good preacher are he should be able to teach in a right and orderly way. Second, he should have a good head. Third, he should be able to speak well. Fourth, he should have a good voice. Fifth, a good memory. Sixth, he should know when to stop. Seventh, he should be sure of his material and be diligent. Eighth, he should stake body and life, goods and honor in it. Ninth, he must suffer himself to be vexed and flayed by everybody.