“An unlucky rich man is more capable of satisfying his desires and of riding out disaster when it strikes, but a lucky man is better off than him…He is the one who deserves to be described as happy. But until he is dead, you had better refrain from calling him happy, and just call him fortunate.”
Herodotus (trans. Robin Waterfield) The Histories Bk. 1, ch. 32, pp. 15-16.
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Solón 17
Athenian legislator -638–-558 BCRelated quotes

“Let no man be called happy before his death. Till then, he is not happy, only lucky.”

“Call no day happy 'til it is done; call no man happy til he is dead.”
Solzhenitsyn here seems to be paraphrasing Sophocles who expresses similar ideas in Oedipus Rex. This is also a direct reference to Plutarch's line, "call no man fortunate until he is dead," from his "Parallel Lives".
The Oak and the Calf (1975)
The Great Chain of Life (1956), Chapter 9 "The Vandal and the Sportsman" http://books.google.com/books?id=Ydc0cooCB6QC&lpg=PA146&q="when+a+man+wantonly+destroys+one+of+the+works+of+man+we+call+him+vandal+when+he+wantonly+destroys+one+of+the+works+of+god+we+call+him+sportsman"#v=onepage. Iowa City: University of Iowa Press, 2009, p. 148.

Il ne savait rien, ne voulait rien savoir, en quoi il se conformait à son génie, dont il ne surchargeait point l’aimable petitesse, et son heureux instinct lui conseillait de comprendre peu plutôt que de comprendre mal.
La Révolte des Anges http://fr.wikisource.org/wiki/La_R%C3%A9volte_des_anges_-_1 [The Revolt of the Angels], (1914), ch. I
Source: Dictionary of Burning Words of Brilliant Writers (1895), p. 345.

A coup sûr, cet homme, tel que je l'ai dépeint, ce solitaire doué d'une imagination active, toujours voyageant à travers le grand désert d'hommes, a un but plus élevé que celui d'un pur flâneur, un but plus général, autre que le plaisir fugitif de la circonstance. Il cherche ce quelque chose qu'on nous permettra d'appeler la modernité; car il ne se présente pas de meilleur mot pour exprimer l'idée en question. Il s'agit, pour lui, de dégager de la mode ce qu'elle peut contenir de poétique dans l'historique, de tirer l'éternel du transitoire.
IV: "La modernité" http://fr.wikisource.org/wiki/La_Modernit%C3%A9
Le peintre de la vie moderne (1863)