"How beautiful it is to do nothing and then rest afterwards.”So says the Spanish proverb, loaded as it is with spiritual instruction on humility, the passing of time, the transience of footprints on the beach. Beautiful, perhaps, but difficult.When I retired from the practice of big-firm law on Feb. 1, people said to me, “Now you’ll have lots of time for writing,” and I assured them that with launching my newest novel, “Saluting the Sun” (Ampersand April, 2015), working on a new …