In Perowne's commentary on the Psalms in one volume, he quotes Calvin on page 445 in his treatment of Psalm 56.
"Assuredly," says Calvin, "this is the true test and proof of our faith; when fears harass us, so far as our fleshly nature is concerned (pro sensu carnis), but do not overthrow and unsettle our minds. It seems, indeed, as if fear and hope were feelings too contrary the one to the other to dwell in the same heart; but experience shows that Hope there in fact really reigns where some portion of the heart is possessed by Fear. . . ."
He goes on for a few more sentences. Where in Calvin's writings did he in fact write this? Thanks!