The Law of Frederic the Great

It is told that Rav Yaakov Tzvi would not normally attend a wedding unless he knew that the young couple would live according to the laws of the Torah. One day an important man who had drifted away from Yiddishkeit asked the Rav to officiate at his daughter's marriage. The Rav knew that the couple did not keep halachah, and he refused.

The man was very influential. He went to the authorities and obtained an order requiring the Rav to perform the marriage. Compelled to comply, the Rav officiated, but instead of saying the words 'according to the law of Moshe and Yisroel,' he declared in a loud voice, 'according to the law of Frederic the Great.'