What is the ruling on one who committed forbidden acts out of ignorance?

Among the leniencies of the religion is the lifting of sin from the one who errs, forgets, or is ignorant, provided he is not negligent, and provided the error is not in what is necessarily known of the religion. This applies if the person had an excuse due to the subtlety of the issue, his recent conversion to Islam, or his living in an environment where knowledge is not readily available.

However, if the accountable person neglects to seek knowledge, he incurs sin for his neglect and for his transgression of the Sacred Law, because seeking knowledge is an obligation. Ignorance is not an excuse when it comes to the rights of people concerning their wealth and blood.