Put the meaning into your own words.

He showed restraint by waiting until the speaker had finished.

The center later chose to rescind an earlier permission to store crates in a corridor after discovering a conflict with another scheduled activity. The exhibition chair questioned the propriety of announcing the change in a public message before informing the artists whose deliveries were affected. She nevertheless exercised restraint in her reply, asking for a practical alternative instead of accusing the staff of deliberately obstructing the event.