What is a serf? What is a serf's duty to their lord?​

A serf could plough his lord's fields, harvest crops, dig ditches, or repair fences. The rest of his time he could take care of his own fields, crops and animals. The big problem for a serf was that he had to do the work for the Lord before he could do his own work.

Explanation:

the catholic church withhold people's access to the bible during the middle ages.

people could go to church and listen to the teachings, but it was absolutely forbidden to own and/or read the books of both the old and new testaments. it was also prohibited to translate the books (which where originally in biblical hebrew) to any other language.

this was done so the church could remain in control of what their teachings were and to enhance their importance and power, while also being able to judge people's actions through information that was unavailable for the general public.