Does the sin increase with the decrease of hardship in committing a sin, and does the reward increase with the increase of hardship in performing an act of obedience?

It is not true that the sin's enormity increases if it is easy to commit; rather, the opposite may be true. For someone who seeks out sin and insists on it, despite its difficulty and the arduousness of its paths, their sin might be more severe and their punishment greater, like "an old adulterer, a lying king, and an arrogant poor person." This is because they committed the sin despite weak motives for it and being able to do without it, which indicates their contempt for Allah's right.

A major sin may be accompanied by matters such as shame, fear, and reverence, which make it like a minor sin. Conversely, a minor sin may be accompanied by a lack of shame, indifference, and disdain, which makes it a major sin. Persistence in committing minor sins may be more grave than committing grave sins.

As for obedience, its reward increases with the hardship accompanying it, such as performing ablution thoroughly despite difficulties and taking many steps to the mosques.