Here is a saying by St Mark the Ascetic:

If we see someone who certainly sins and does not repent, without anything bad happening to him even until he dies, be sure that God’s judgment for him will be merciless. (in Greek)

St Mark the Ascetic is one of the most significant Fathers included in a collection of Greek patristic texts known as Philokalia. The saying belongs to a “cycle” answering the question why some people suffer and others not.

If what we call misfortunes – illness, poverty, etc – provide for us mercy in the final judgment, why God prefers to deny this mercy to some people, and gives them goods even when they sin?