heart of grace

noun1

1. •
   (no longer used) Chiefly preceded by get, give, take, etc.: courage or relief, especially when gained as a result of favour shown to one.

   • Rise therfore Euphues, & take heart at grasse, younger yͧ [thou] shalt neuer be: plucke vp thy stomacke, if loue it selfe haue stoung thée it shal not stifle thée. — 1578