The Collaborative International Dictionary of English v.0.48:

Prosper \Pros"per\, v. t. [imp. & p. p. Prospered; p. pr. &
   vb. n. Prospering.] [F. prosp['e]rer v. i., or L.
   prosperare, v. i., or L. prosperare, v. t., fr. prosper or
   prosperus. See Prosperous.]
   To favor; to render successful. "Prosper thou our handiwork."
   --Bk. of Common Prayer.
   [1913 Webster]

         All things concur toprosper our design.  --Dryden.
   [1913 Webster]