And please note that your are asking for three, not two, separate quotations ("Pericles," Xenophon, and Theocritus), so you would normally need three separate posts.
However, before posting anything, it's a good idea to consult our search engine (above box). Because these are popular quotations, you might find your question has already been answered, e.g. your first request: http://www.translatum.gr/forum/index.php?topic=84929.0
So for the nonce, we'll answer one of your requests, "As long as we hope, we live." That's from Theocritus, Idyll
4, verse 42:ἐλπίδες ἐν ζωοῖσιν
— literally, "Hopes exist among the living."