|1.||preaching to the choir|
Preaching to the choir means you are trying to make believers out of people who already believe, or convince people who are already convinced.
"We could start a new tradition, Birthdays without Boyfriends. It could work."
"Preachin' to the choir here baby."
|2.||preaching to the choir|
Extolling/defaming a cause to people convinced of it's greatness/horridness. Etymology is obviously from christian church choirs.
Playmate: Sex sells
Hugh H: Preaching to the choir.