Wartet nur! [Only Wait!] in Poems for the Times ; also in Poems of Heinrich Heine: Three Hundred and Twenty-five Poems (1917) Selected and translated by Louis Untermeyer, p. 263

“Do not smile at my advice -- the advice of a dreamer who warns you against Kantians, Fichteans, and philosophers of nature. Do not smile at the visionary who anticipates the same revolution in the realm of the visible as has taken place in the spiritual. Thought precedes action as lightning precedes thunder. German thunder is of true Germanic character; it is not very nimble, but rumbles along ponderously. Yet, it will come and when you hear a crashing such as never before has been heard in the world's history, then you know that the German thunderbolt has fallen at last. At that uproar the eagles of the air will drop dead, and lions in the remotest deserts of Africa will hide in their royal dens. A play will be performed in Germany which will make the French Revolution look like an innocent idyll.”

Heinrich Heine

"The History of Religion and Philosophy in Germany" (1834)

“So we keep asking, over and over,
Until a handful of earth
Stops our mouths —
But is that an answer?”

Heinrich Heine

Lazarus, I (1854)

“Hence the one-sided errors—ces erreurs d'idée fixe—which we cannot escape when we stand too near to one or the other party; either deceives, yet does it unaware, and we confide most willingly in those who think as we do. But if we are by chance of such indifferent nature that we, without special predilection, keep in continual intercourse with all, then we are bewildered by the perfect self-confidence of either party, and our judgement is neutralised in the most depressing manner.”

Heinrich Heine

French Affairs page 156
The Romantic School (1836)

“Although the Protestant Church is accused of much disastrous bigotry, one claim to immortal fame must be granted it: by permitting freedom of inquiry in the Christian faith and by liberating the minds of men from the yoke of authority, it enabled freedom of inquiry in general to take root in Germany, and made it possible for science to develop independently. German philosophy, though it now puts itself on an equal basis with the Protestant Church or even above it, is nonetheless only its daughter; as such it always owes the mother a forbearing reverence.”

Heinrich Heine

Wenn man auch der protestantischen Kirche manche fatale Engsinnigkeit vorwirft, so muß man doch zu ihrem unsterblichen Ruhme bekennen: indem durch sie die freie Forschung in der christlichen Religion erlaubt und die Geister vom Joche der Autorität befreit wurden, hat die freie Forschung überhaupt in Deutschland Wurzel schlagen und die Wissenschaft sich selbständig entwickeln können. Die deutsche Philosophie, obgleich sie sich jetzt neben die protestantische Kirche stellt, ja sich über sie heben will, ist doch immer nur ihre Tochter; als solche ist sie immer in betreff der Mutter zu einer schonenden Pietät verpflichtet.
Source: The Romantic School (1836), p. 24

“I am speaking of the religion whose earliest dogmas contain a condemnation of the flesh, and which not merely grants the spirit superiority over the flesh but also deliberately mortifies the flesh in order to glorify the spirit. I am speaking of the religion whose unnatural mission actually introduced sin and hypocrisy into the world, since just because of the condemnation of the flesh the most innocent pleasures of the senses became a sin and just because of the impossibility of our being wholly spirit hypocrisy inevitably developed.”

Heinrich Heine

Ich spreche von jener Religion, in deren ersten Dogmen eine Verdammnis alles Fleisches enthalten ist, und die dem Geiste nicht bloß eine Obermacht über das Fleisch zugesteht, sondern auch dieses abtöten will, um den Geist zu verherrlichen; ich spreche von jener Religion, durch deren unnatürliche Aufgabe ganz eigentlich die Sünde und die Hypokrisie in die Welt gekommen, indem eben durch die Verdammnis des Fleisches die unschuldigsten Sinnenfreuden eine Sünde geworden und durch die Unmöglichkeit, ganz Geist zu sein, die Hypokrisie sich ausbilden mußte.
Source: The Romantic School (1836), p. 3

“The fundamental evil of the world arose from the fact that the good Lord has not created money enough.”

Heinrich Heine

As quoted in The Pillars of Economic Understanding : Factors and Markets (2000) by Mark Perlman and Charles Robert McCann

“If one has no heart, one cannot write for the masses.”

Heinrich Heine

Letter to Julius Campe (March 18, 1840)

“Music is a strange thing. I would almost say it is a miracle.”

Heinrich Heine

Letters on the French Stage (1837)

“I had once a beautiful fatherland.
The oak tree
Grew so high there, violets nodded softly.
It was a dream.It kissed me in German and spoke in German
(You would hardly believe
How good it sounded) the words: "I love you!"
It was a dream.”

Heinrich Heine

<p>Ich hatte einst ein schönes Vaterland.
Der Eichenbaum
Wuchs dort so hoch, die Veilchen nickten sanft.
Es war ein Traum.</p><p>Das küßte mich auf deutsch und sprach auf deutsch
(Man glaubt es kaum
Wie gut es klang) das Wort: "Ich liebe dich!"
Es war ein Traum.</p>
In Der Fremde (In a Foreign Land)

“What! Think you that my flashes show me
Only in lightnings to excel?
Believe me, friends, you do not know me,
For I can thunder quite as well.”

Heinrich Heine Wartet nur

Wartet nur! [Only Wait!] in Poems for the Times ; also in Poems of Heinrich Heine: Three Hundred and Twenty-five Poems (1917) Selected and translated by Louis Untermeyer, p. 262

“Money bequeathed to my wife "on the express condition that she remarry. I want at least one person to be truly bereaved by my death."”

Heinrich Heine

Testamentary Will of Heinrich Heine (1856); no published source for this has been located.
Disputed

“Rossini, divine master.”

Heinrich Heine

Heinrich Heine's Pictures of Travel (1855) as translated by Charles Godfrey Leland, p. 270

“Splendid if I overcome
My earthy passion,
But if I succeed not,
Still I have known happiness!”

Heinrich Heine

“He who will establish himself on a certain height must yield according to circumstances, like the weather-cock on a church-spire, which, though it be made of iron, would soon be broken by the storm-wind if it remained obstinately immovable, and did not understand the noble art of turning to every wind. But a great man will never so far contradict his own feelings as to see, or, it may be, increase, with cold-blooded indifference, the misfortunes of his fellow country-men.”

Heinrich Heine

English Fragments (1828), Ch. 11 : The Emancipation
Variant: The weather-cock on the church spire, though made of iron, would soon be broken by the storm-wind if it did not understand the noble art of turning to every wind.