In the living room of a sprawling house on the edge of Sioux Falls, Mendel Alperowitz is winding a leather strap around the arm and fingers of Stuart Jacobs.
A box attached to the strap rests in Jacobs' elbow; inside is a scroll inscribed with seminal Jewish prayers that proclaim one God and profess man's duty to love that God. Another box rests on his forehead. They are performing the Jewish ritual of tefillin at Jacobs' home.
Alperowitz leads Jacobs in a prayer he once had memorized.
"V'ahavata. Et. Adonai. Elohecha. B'chol. L'vavcha," Alperowitz says and Jacobs repeats. "You shall love your God with all your heart."
When the prayer is over, Alperowitz takes out a ram's horn, a shofar, through which he blows a series of long and short blasts.
Jacobs, 55, takes it in with a wide grin.
"It always makes me feel better to do tefillin," Jacobs said, "because it takes me back to where I belong."
Jacobs, who was born and raised in the Bronx, is part of a tiny community of Sioux Falls Jews that has long gathered to pray and commune without a permanent rabbi. The last full-time spiritual leader of Mount Zion — the only synagogue in South Dakota east of the Black Hills — retired in 1978.