I begin to see that a man's got to be in his own heaven to be happy.
(Mark Twain [Samuel Langhorne Clemens] (1835-1910), U.S. author. 1907. Eli Stormfield, in "Extracts from Capt. Stormfield's Visit to Heaven," p. 835, Mark Twain: Collected Tales, Sketches, Speeches, & Essays, 1891-1910, Library of America (1992).)
The "kingdom of heaven" is a condition of the heartnot something that comes "above the earth" or "after death."
(Friedrich Nietzsche (1844-1900), German philosopher, classical scholar, critic of culture. Friedrich Nietzsche, Sämtliche Werke: Kritische Studienausgabe, vol. 6, p. 207, eds. Giorgio Colli and Mazzino Montinari, Berlin, de Gruyter (1980). The Antichrist, section 34 (prepared for publication 1888, published 1895).)