and I wouldn't suggest killing him, will make you threatingly with the mobs and not able to traverse PoSky easily (or do any quests). Also no way to get Inhabitants of Sky faction back up that I have found.
He is not the actual quest giver... you hail him and he asks you who you wish to be tested by. He then hands you a book that you hand back to him which spawns the correct turn in person. Be sure you hail the spawned npc to verify you have the correct one for the quest you are doing.
What island is he on ? 1st? 2nd? 3rd? 4th? 5th? 6th? 7th? I am working on some quest in PoA. And say I do get the 3 things for the ring, do I just give him the 3 items ? and he gives me a ring ? will he atack me once I give him the 3 items ??