For the past five years, I have had the privilege of serving as president of Park Avenue Synagogue, the largest Conservative congregation in New York City. On most Shabbat mornings, I sit on the bima in our magnificent sanctuary listening to our rabbis and cantors. The elegant surroundings complement and enhance our centuries-old ritual. We pray, meditate, study the weekly Torah reading, take pride in the proficiency of our bnei mitzva, say kaddish for a loved one. But sometimes, my mind drifts backward in time to other synagogues, other sanctuaries that I can only imagine. On June 22, 1943, my father, Josef Rosensaft, was on a transport from his hometown of Bedzin in southern Poland to Auschwitz. The son and grandson of devout hassidim, followers of the rabbis of Ger, he had become a labor Zionist and one of the few Jewish members of a local sports club. On this occasion, the train used by the Germans to deport Jews to the death camp was not made up of windowless cattle cars but consisted of normal passenger cars. My father, an excellent swimmer, escaped by diving out of one of the train's windows into the Vistula River. Although wounded by three German bullets, he was able to return early the next morning to Bedzin where his father was waiting for him. Six weeks later, during the liquidation of the Bedzin Ghetto, my grandfather died of natural causes in my father's arms. After my father had buried his father, he fled to the nearby town of Zawiercie. At the end of August, he was deported from there to Auschwitz-Birkenau. In mid-October 1943, during Succot, my father smuggled a tiny apple into the Birkenau barrack where the inmates had gathered to pray so that the highly respected Rabbi of Zawiercie, known as the Zawiercier Rov, could recite the Kiddush blessings. Throughout the prayers, my father recalled, the aged Rov stared at the apple, obviously conflicted. At the end of the clandestine service, he picked up the apple and said, in Yiddish, almost to himself, "In iber dem zol ikh itzt zogn, 've-akhalta ve-savata u-verakhta et Hashem Elohekha...' (And over this, I should now say, 'And you will eat, and you will be satisfied, and you will bless your God...'). "Kh'vel nisht essen (I will not eat)," he went on, "veil ikh vel nisht zat sein (because I will not be satisfied), un ikh vill nisht bentchn (and I refuse to say the Grace After Meals)." And with that, he put down the apple and turned away. The rabbi never lost his faith in God. Like the hassidic master, Levi Yitzhak of Berditchev, however, he was profoundly, desperately angry with Him, and this anger caused him to confront God from the innermost depths of his being. One evening around the same time, my father and a group of Jews from Zawiercie were sitting in their barrack when the Zawiercier Rov suddenly said, again in Yiddish, "You know, der Ribboine shel-oilem ken zein a ligner" (the Master of the Universe can be a liar). Asked how this could possibly be, the rabbi explained, "If God were to open His window now and look down and see us here, He would immediately look away and say, 'Ikh hob dos nisht geton'" (I did not do this) - and that, he said, would be the lie. THE FOLLOWING year, my father was an inmate in the notorious Block 11, also known as the Death Block, at Auschwitz. He had been there for more than five months, ever since he had been brought back to Auschwitz after escaping from a labor camp to which he had been transferred and hiding in Bedzin for six weeks with a Polish friend. Throughout his imprisonment in Block 11, he had been continuously tortured. The Germans wanted him to betray the Poles who had helped him escape and who had hidden him, something he steadfastly refused to do. Millions of European Jews had already perished. Thousands were dying daily. It was the most unlikely setting for prayer and devotion to God. And yet that night, the Jewish kapo in charge of Block 11 wanted my father to conduct the Yom Kippur service. Half-naked, emaciated, starved, my father chanted Kol Nidre from memory in the Death Block of Auschwitz, and led the prayers there that evening and the following day for his fellow prisoners. As a reward, the kapo gave my father and the other inmates of Block 11 an extra bowl of soup to break the fast. A barrack in Birkenau during Succot, 1943, and Block 11 in Auschwitz on Yom Kippur, 1944, became synagogues for a few hours, sanctuaries for Jews, many about to die, fleeting refuges from horror and agony, where my father and the Zawiercier Rov simultaneously reached out to and defied God. AT THE outset of the 21st century, Jews throughout the world are blessed to be able to gather and pray publicly in comfort and safety. Still, we should remind ourselves every once in a while, as we sit in our elegant synagogues, that the essence of our identities and of our prayers emanate from deep within our souls. I would like to believe that there are moments when my prayers, our prayers, transcend the years to merge with those that rose out of Block 11 and a Birkenau barrack, and that together they somehow reach their destination. The writer, a New York lawyer, is president of Park Avenue Synagogue in Manhattan and founding chairman of the International Network of Children of Jewish Holocaust Survivors.