Again, one of my favourite Nietzsche quotes -- self-contradiction included :)
Let us finally consider how naive it is altogether to say: "Man ought to be such and such!" Reality shows us an enchanting wealth of types, the abundance of a lavish play and change of forms — and some wretched loafer of a moralist comments: "No! Man ought to be different." He even knows what man should be like, this wretched bigot and prig: he paints himself on the wall and comments, "Ecce homo!" But even when the moralist addresses himself only to the single human being and says to him, "You ought to be such and such!" he does not cease to make himself ridiculous. The single human being is a piece of fatum from the front and from the rear, one law more, one necessity more for all that is yet to come and to be. To say to him, "Change yourself!" is to demand that everything be changed, even retroactively. And indeed there have been consistent moralists who wanted man to be different, that is, virtuous — they wanted him remade in their own image, as a prig: to that end, they negated the world! No small madness! No modest kind of immodesty!
Morality, insofar as it condemns for its own sake, and not out of regard for the concerns, considerations, and contrivances of life, is a specific error with which one ought to have no pity — an idiosyncrasy of degenerates which has caused immeasurable harm.
We others, we immoralists, have, conversely, made room in our hearts for every kind of understanding, comprehending, and approving. We do not easily negate; we make it a point of honor to be affirmers. More and more, our eyes have opened to that economy which needs and knows how to utilize everything that the holy witlessness of the priest, the diseased reason in the priest, rejects — that economy in the law of life which finds an advantage even in the disgusting species of the prigs, the priests, the virtuous. What advantage? But we ourselves, we immoralists, are the answer.
Twilight of the Idols, "Morality as anti-nature," § 6.