"Astronauts usually are allowed a very limited number of personal items on their missions, yet Chamitoff insisted on taking both mezuzahs with him on the six-month long mission. “They represent the two most important elements in his life: Space and the Jewish faith,” noted Cowan."

as a paraphrase on Einstein's saying, i would say that:
Only two things are infinite, the universe and human oddity, and I'm not sure about the former.