finally understood the difference between these two today when Herman explained it in the sermon.
Mercy is withheld punishment | undeserved pardon | not getting what you deserve and Grace is unmerited favour | getting what you dont deserve.
most of the time, when I read about His grace and mercy, i only got the first half of it. but today, i realized the other half of it. I was pardoned from the penalty of sin and then showered with an abundant of love. And Im in awe again thinking of God. He not only loves, but He loves beyond what we could ever hope for!