“God loves to show mercy. He is not hesitant or indecisive or tentative in his desires to do good to his people. His anger must be released by a stiff safety lock, but his mercy has a hair trigger.
That is what is meant when he came down on Mount Sinai and said to Moses, “The LORD, the LORD, a God merciful and gracious, slow to anger, and abounding in steadfast love” (Exodus 34:6). The point is the contrast between the sluggishness of his anger and the effusiveness of his love.
-John Piper, The Pleasures of God: Meditations on God’s Delight in Being God, 173.