Not his STEWARD...
Game of Thrones Season 1, Episode 7
You're a STEWARD, Snow, not a ranger.
Game of Thrones Season 2, Episode 5
I was his STEWARD. In fact...
Game of Thrones Season 6, Episode 7
Mormont himself chose Jon to be his STEWARD.
Game of Thrones Season 5, Episode 2
made that man his STEWARD.
Game of Thrones Season 6, Episode 7