God also made it clear to Blessed Anne Catherine Emmerich about his justice and mercy in this vision.
She said, "Great is God's justice, but still more inconceivable is his mercy. He damns only those who are determined not to be converted; they who have a spark of good will are saved. Those who grieve for their sins, confess them sincerely, and trust confidently in the merits of their Savior; they are saved and their sins will no longer be remembered. It's true that they go to purgatory, but not to remain long. On the other hand, many stay long in purgatory who, although not great sinners, have lived tepidly. Through pride they would take no admonition or instruction from their confessor. The time was when the thought of only one poor sinner's condemnation grieved me so that I could not get over it; but on the present occasion, though many were condemned, I was perfectly calm, for I saw that God's justice called for it."
(Those last lines really helped me.)