While the terms have similar meanings, grace and mercy are not the same. To summarize the difference: mercy is God not punishing us as our sins deserve, and grace is God blessing us despite the fact that we do not deserve it. read more
In short, mercy is God not giving us what we do deserve; grace is God giving us something we do not deserve. In Habakkuk 3:2, the prophet asks the Lord to "in wrath remember mercy." Despite God's judgment, He asked for God to relent and not pour out the full wrath they deserved. read more