Is a Muslim held accountable for what he has learned of Sharia, or for all Sharia rulings?

It is from the mercy of Allah Almighty that He does not hold His servants accountable except for what of the Sharia (Divine Law) has reached them, as He states: "{that I may warn you thereby and whoever it reaches}", and "{And never would We punish until We had sent a messenger}", "{so that mankind would have no argument against Allah after the messengers}".

However, whoever falls short in learning what is obligatory for him of the rulings of the Sharia is sinful, because it is incumbent upon every Muslim to learn what is religiously required of him. The ignorant person is excused if he did not neglect seeking knowledge.

Thus, whoever commits an act whose prohibition is disputed without asking people of knowledge is sinful for neglecting to learn. And whoever commits what is unanimously agreed upon as prohibited, or neglects what is unanimously agreed upon as obligatory, while being negligent in learning, is even more deserving of sin.