I've completed all the quests for Proving Honor, it's on completed quests but it's not actually completed. Return to Jorrvaskr diamond is not filled in. When I try to continue in the game asking for work he says he already gave me work when I am finished. I can't use console commands because I'm playing on a PS4, so how do I continue in the companions story. I did the ceremony where he swears loyalty to me but it still doesn't let me continue in the story.
It sounds like you've encountered a known bug, with no known solution.
The quest registers as completed in the journal, before being completed, making the next quest in the series impossible to initiate.
Since you're playing on PS4, you'll need to load a prior save. If you don't have one, then you'll have to either give up on the Companions quest line or start a new character.
This is an Elder Scrolls game. Make saves often, at key points.
Ok my friend fond a way to fix this it is strange and takes some time but it works you have to make a new person and name him dadric then do the companion quests up to when you kill the silver hand and kill them with a silver sword head back to whiterun save it and go back to your world and you will have a new mission called family alum that is your next companion mission I did this myself so I know it works