These are the contexts of the quotes tweeted from @sueannbowling between July 24 and July 30, 2014. All but the last are from The Two Towers, by J.R.R. Tolkien.
“Trust not to secret ways.” Theoden to Eomer, warning that Sauruman may have scouted out the hidden paths in Helm’s Deep.
“The world changes, and all that was strong now seems unsure.” Theoden, usure of the safety of the “unconquerable” Hornburg after the Deeping Wall has fallen.
“One who cannot cast away a treasure at need is in fetters.” Aragorn to Pippin, as he returns the brooch Pippin cast away as a sign to any tracker.
“Luck served you there, but you seized your chance with both hands.” Gimli, referring to the cutting of the bonds on the hobbits’ wrists.
“It is difficult to know with these evil folk when they are in league, and when they are cheating one another.” Aragorn, referring to the question of whether Sauruman and Sauron are working together or in rivalry. Note that this and the two previous quotes are at Isengard, after its overthrow by the Ents.
“Just wait until you get hungry enough.” Sue Ann Bowling, Homecoming. Marna to Cinda, after Cinda has found a very strange looking creature she hopes in inedible. (They are stranded on Mirror, without food.)