A Hadith says that Abu Bakr has more Iman than the rest of ummah because of purity of heart.
There are plenty of people that want a pure heart but they can't. It is striking that many of the people that have converted to Islam or become practicing Muslims have come from the world of adultery.
In contrast there are plenty of people that haven't committed adultery a single time and sacrificed their entire wealth for the education of their children yet they hate and insult Islam in the most horrible manner. I have seen many cases myself.
My question is: What is the connection of exterior deeds like watching porn, backbiting or good deeds like reading Quran, giving sadaqa, dhikr and the properties of the heart that upon the properties of the heart God will value our deeds on the day of judgment? Sometimes it looks like sins soften your heart.
Example: When you are angry instead of venting your anger towards your parents you commit a much smaller sin through releasing this anger through watching porn. And after watching porn you feel fit for spending the entire day learning about Islam or reading Quran. Otherwise the entire day passes in a bad spiritual situation like anger or dissatisfaction and because of that you cannot learn anything about islam during the entire day and are tempted to commit sins far bigger than watching porn because of the bad spiritual situation of anger and dissatisfaction.