(137). “Indeed, those who believe, then disbelieve, then believe, then disbelieve, and then increase in disbelief—Allah will neither forgive them nor guide them to any path.”

That is, whoever repeatedly disbelieves after having believed—being guided and then going astray, seeing and then becoming blind, believing and then disbelieving—and persists and increases in his disbelief is far removed from divine aid and guidance to the straightest path. He is also far removed from forgiveness because he has committed the greatest impediment to attaining it. His disbelief becomes a punishment and an indelible seal, as Allah Most High says: “So when they deviated, Allah caused their hearts to deviate,” and: “We turn their hearts and their eyes away, just as they refused to believe in it the first time.”

The verse also indicates that if they do not increase in disbelief, but instead return to faith and abandon the disbelief they have embraced, Allah will forgive them, even if they have repeatedly apostatized.

Since this is the ruling concerning disbelief, it applies all the more readily to sins of a lesser degree: however often a servant commits them, if he then returns to repentance, Allah will once again grant him forgiveness.