What is the ruling on trivializing minor sins like lying and sleeping through the Fajr prayer, and believing that good deeds erase these transgressions?

The correct path is for a person not to look at the smallness of the sin, but rather to look at the greatness of the One he has disobeyed. Allah holds His servants accountable even for the smallest particles, for "whoever does an atom's weight of good will see it, and whoever does an atom's weight of evil will see it." Just scales will be set up on the Day of Resurrection. Persistence makes a minor sin a major one. Trifling acts and minor sins have their reckoning and punishment. When they accumulate, they destroy their perpetrator because they have a claimant from Allah. Trifling sins are those which a person does not care about, and they darken and blacken the heart if one does not repent from them. Falling into minor sins is one of Satan's steps towards falling into major sins. Allah Almighty has commanded believers to enter into Islam completely and not to follow the footsteps of Satan, for he is a clear enemy. He has warned against faltering after clear proofs have come, for Allah is All-Mighty, All-Wise, and He punishes the disobedient according to His wisdom.