There are many font sites on the web.
Try 1001fonts.com -- I think the calligraphic ones are what you want -- maybe Black Chancery or Carolingia under "Calligraphy."
Maybe Michaelmas under "Script."
The verse in question appears in the Vulgate as:
sed et si ambulavero in valle mortis non timebo malum quoniam tu mecum es
"mos" can mean "will" but in the sense of "wish" -- although it usually means "custom." I am thinking that "sententia" here means "will" as well, but it is usually translated as "opinion." Neither of these words indicate future tense.
-- O tempora! O mores! - Cicero.
-- Quot homines, tot sententiae - Terence.