Some people (especially the older ones) are very prone to give other people moral advice. And I search for how to call somebody who is doing this so extensively that his environment is just exhausted (sick of it) from hearing that much advices.
Example: If a group of boys would try to return their ball of a neighbor by themselves, he would point out that it's not a good decision and they should rather ask the neighbor. If a group of students have to do the homework together and someone has the solution for it, he would point out, that this is morally not alright and they should do it by themselves.