im not sure if i understand your post correctly...
but i recall that Divine trait doesn't give anything, but it allows you to equip Divine tools, they can be found in certain areas in the island or can be bought from the church.
1- You must do the Catacomb quest with Cocona present.
2- in the end of the dungeon there is a friendly skeleton, who will not attack you, if you talk to it with Cocona present and DO NOT ATTACK THE FRIENDLY SKELETON!
3- this should be it, a little story will roll and you will get the idol of the believer.
the fandom wiki is pretty spot on and it also has images, you should refer to it, but the missing point from there is that you shouldn't kill the friendly skeleton.
Edit: nvm it does say that you shouldn't kill the skeleton.