God demands truthfulness of His people. God proves true in His promises. Genuine benevolence gives not for what it can get. It is not concerned about itself, but solely about the other. This is the meaning of agape 2.
Grace is benevolence without regard to desert, indeed, notwithstanding ill desert.
Where grace contemplates humans as sinful, guilty and condemned, mercy sees them as miserable and needy. God is forbearing and longsuffering in His love 2. On the one hand, God's justice seems so severe, with the slightest sin earning eternal damnation. On the other hand, God is said to be love itself. God's justice is not without love, prompting Him to make a way for us to escape judgment.