How does Keller define corporate gospel renewal? 

when many members of a business organization experience gospel renewal together, and begin attending the same church as a result. 

A season in which a whole body of believers experiences personal gospel renewal together. 

A large event, usually outdoors, such as a rally or crusade where vast numbers of people hear the gospel and experience conversion.

When the gospel message is changed and reconfigured to appeal more to a particular demographic.