On Sunday evening, 300 leading members of the Jewish community in Berlin, Germany, took part in a grand dinner organized by Chabad. Local shliach Rabbi Yehuda Teichtel held his audience spellbound as he related what his grandfather’s reaction was when he first took on his shlichus: “At first, my grandfather asked me, ‘How can you possibly go back to the place where all my family was murdered?’ Then, after a few moments of reflection, he observed: ‘Actually, this is the greatest revenge you could possibly have upon the Nazis. Go there in peace, and I hope you will be very...