Chief Rabbi Lord Sacks recalled the "great personal debt" he owed B'nai B'rith when he addressed the centenary dinner of B'nai B'rith First Lodge.
He told the 320 guests at the Great Hall in Lincoln's Inn, central London, that his decision to become a rabbi had been influenced by a travel bursary awarded by the First Lodge in 1968.
This, together with a college prize, "enabled me to spend two months in America in the summer of that year, meeting many of the leading thinkers of American Jewry. That trip changed my life. Because of it, I eventually decided to become a rabbi and dedicate my life to serving the Jewish community.
"I am sure there are many others who could tell a similar story. B'nai B'rith encouraged Jews to become leaders - and it still does."
Lord Sacks was presented with the lodge's centenary award by its president, Martin Aaron. Israeli envoy Ron Prosor also spoke and the dinner was attended by B'nai B'rith leaders from many other European countries.