BEVERLY — As a young boy in Lithuania, Samuel Bak witnessed the worst of humankind when his father, four grandparents, uncles, aunts and 7-year-old best friend were murdered in the Holocaust. The experience has helped define his work as an artist and painter for the last eight decades. "I realized that I had a story to tell, an almost sacred duty to fulfill," Bak said. "I had to show my murdered family that in me they were forever alive, that I could carry the weight of their expectations that they so lovingly put on my shoulders and tell their tragic...