Speech of Ayatullah Muhammad Javad Fazel Lankarani on the implications of sins according to a hadith from Imam Reza (as)

There is a hadith from Imam Reza (as) in Mizan al-Hikmah according to which the Imam has been quoted to have said, “Keep away from sins because sins destroy the good. Verily a man commits a sin and because of that he forgets the knowledge he had learned.”

Sins have implications. Repentance lifts the worldly punishment and the sin will be forgiven but one’s soul will not be like it was before. After being polluted by a sin, the soul loses its previous capacity, clarity and fineness and no matter how one tries after that he may not acquire the same status he had before committing the sin. 

According to hadith if one devotes himself to God for forty days, God will open fountains of wisdom toward his heart. This means that his soul will blossom and give out its fruits but if he commits sins, he will be deprived of these results.

Source: Mizan al-Hikmah, 3/465.