While I appreciate Prof. Barash’s candour (and nothing I write here should be construed as a personal attack on him or his ilk), nevertheless, Materialists have for decades (if not centuries) been making promises like, “I am also nearly as confident that some day, we’ll understand how.” It even has a name, “Promissory Materialism“!
And make a point to go read his series of posts, Shroud of Turin: Burial sheet of Jesus by starting with #1 in his October archives and moving into November.