The annual CST dinner was not just any dinner.
For the Chancellor, George Osborne, it was also his bar mitzvah.
During the speech, by Daniel Taub, the Israeli Ambassador reached under the table and pulled out an exquisitely wrapped box to hand to the Chancellor.
It was, Mr Taub told him, a bar mitzvah present.
Mr Osborne has spoken before about how much he wished he had been bar mitzvah.
The Chancellor was clearly touched. "Thank you for my bar mitzvah present", he said to the Ambassador. "I have waited 27 years for that.
"But hey - what a bar mitzvah!"