to preach to the choir
01
to attempt to make people accept ideas, opinions, etc. that they already agree with
Dialect
American
American
Idiom
Informal
例
The political candidate's speech at the rally was well-received, but some argued that it was preaching to the converted since the attendees already supported their campaign.
The professor's lecture on the benefits of exercise in a sports science class seemed like preaching to the choir, as the students were already knowledgeable on the topic.
