There are a few conundrums in the islamic view of sin as I see it.
They keep saying that Allah forgives sins without punishment but if the sin is a crime then sharia punishes with a fine or a flogging or stoning or mutilating someone?
So there is no forgiveness if the sin is a crime.
Secondly if some human act is not a crime and there is no punishment by Allah then why bother calling it a sin in the first place? It may not be the best behaviour but it is not a sin because there is no punishment. If a fly lands on your arm is the fly committing a sin? It might be a slight annoyance but is it a sin? It’s the same thing with Allah. If some human behaviour causes Allah some slight discomfort like a fly flying around your food in a restaurant is the forgiveness or the sin a big deal? Neither is a big deal is it? If a behaviour is not punished then it is acceptable even if it might be slightly annoying but it doesn’t cause Allah any pain such that he has to punish it. It is just an acceptable imperfection but why call it a sin in that case?
God is not like this in the bible. In the bible there are no small sins. All sins are mortal sins with eternal death as the punishment. Eve took the forbidden fruit. Every sin is a specific disobeying of a commandment to love God with all and our neighbour as ourself . The bar seems to be set a lot lower in Islam so the offence is a lot smaller. As long as a Muslim worships, pays his taxes and keeps his family under control he has done his duty. The biblical God demands a lot more, namely perfection.
It appears to be that there are differences between the concept of sin in the bible and in Islam. These should be born in mind when we are talking about which God is more merciful and forgiving.